Occurrence and fate of benzophenone-type UV ... - ACS Publications

Subscriber access provided by UNIV OF NEW ENGLAND ARMIDALE

Characterization of Natural and Affected Environments

Occurrence and fate of benzophenonetype UV filters in a tropical urban watershed Feijian Mao, Luhua You, Martin Reinhard, YiLiang He, and Karina Yew-Hoong Gin Environ. Sci. Technol., Just Accepted Manuscript • DOI: 10.1021/acs.est.7b05634 • Publication Date (Web): 05 Mar 2018 Downloaded from http://pubs.acs.org on March 7, 2018

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 32

Environmental Science & Technology

1

Occurrence and fate of benzophenone-type UV filters in a tropical urban watershed

2 3 4

Feijian Mao 1, Luhua You 1, Martin Reinhard 2, Yiliang He 3, Karina Yew-Hoong Gin 1,4,*

5 6 7

1

8

1 Engineering Drive 2, E1A 07-03, Singapore 117576, Singapore

9

2

Department of Civil and Environmental Engineering, National University of Singapore,

Department of Civil and Environmental Engineering, Yang & Yamasaki Environment &

10

Energy Building, 473 Via Ortega, Stanford University, Stanford, California 94305, USA

11

3

12

Shanghai 200240, China

13

4

14

Engineering Drive 1, #02-01, Singapore 117411, Singapore

School of Environmental Science and Engineering, Shanghai Jiao Tong University,

NUS Environmental Research Institute, National University of Singapore, 5A

15 16 17

* Corresponding author. Tel.: +65 65168104; E-mail address: [email protected]

18 19

ACS Paragon Plus Environment

1


20

Page 2 of 32

Table of Content

21

22 23


2

Page 3 of 32


24

Abstract: The study investigated the occurrence and fate of seven benzophenone-type

25

UV filters (i.e., 2,4-dihydroxybenzophenone (2,4OH-BP), 2,2’,4,4’-

26

tetrahydroxybenzophenone (2,2’,4,4’OH-BP), 2-hydroxy-4-methoxybenzophenone

27

(2OH-4MeO-BP), 2,2’-Dihydroxy-4,4’-dimethoxybenzophenone (2,2’OH-4,4'MeO-BP),

28

2,2’-Dihydroxy-4-methoxybenzophenone (2,2’OH-4MeO-BP), 4-hydroxybenzophenone

29

(4OH-BP) and 4,4’-dihyroxybenzophenone (4DHB)) in a tropical urban watershed

30

consisting of five major tributaries that discharge into a well-managed basin. Total

31

benzophenone concentrations (∑ C ) varied from 19 to 230.8 ng L-1 in overlying bulk

32

water, 48 to 115 ng L-1 in pore water, 295 to 5813 ng g-1 dry weight (d.w.) in suspended

33

solids, and 6 to 37 ng g-1 d.w. in surficial sediments, respectively. The tributaries (∑ C :

34

19-231 ng L-1) were the main source of benzophenone compounds entering the basin

35

(∑ C : 20-81 ng L-1). In the water column, the vertical concentration profile in the

36

aqueous phase was uniform while concentrations in the suspended solids decreased

37

with depth. Different distribution profiles were also identified for benzophenones in

38

suspended solids and sediments. A preliminary risk assessment suggested that the

39

seven BPs were unlikely to pose ecotoxicological risks to local aquatic organisms

40

except for 2OH-4MeO-BP in the case of an intermittent release.

41 42

Keywords: Benzophenones; bulk water; suspended solids; Pore water; Sediments

43


3


44

Page 4 of 32

1 Introduction

45 46

A variety of benzophenone compounds (BPs) have been used as ultraviolet (UV) light

47

absorbers in personal care products (e.g. sunscreens, shampoos, body lotions and hair

48

sprays) and synthetic products such as insecticides, plastic bags and paints that are

49

exposed to sunlight.1–3 In Australia, Europe and China, 2-hyrdoxy-4-

50

methoxybenzophenone (2OH-4MeO-BP) has been approved for use as an active

51

ingredient in sunscreens at concentrations up to 10%.4 Other countries have permitted

52

the use of 2,4-dihydroxybenzophenone (2,4OH-BP), 2,2’,4,4’-

53

tetrahydroxybenzophenone (2,2’,4,4’OH-BP), 2,2’-Dihydroxy-4,4’-

54

dimethoxybenzophenone (2,2’OH-4,4'MeO-BP), and 2,2’-dihydroxy-4-methoxy-

55

benzophenone (2,2’OH-4MeO-BP) in sunscreens.4,5 Due to extensive use, BP-type UV

56

filters can enter water environments directly from recreational activities (e.g. bathing and

57

swimming) and indirectly from sewage discharges (e.g. wastewater treatment plant

58

effluent and domestic washing).2,6,7

59 60

Various studies have demonstrated the estrogenic activity of BPs and thus they are

61

currently regarded as potential endocrine disrupting chemicals.6,8,9 For example, studies

62

have demonstrated the weak estrogenicity of 2OH-4MeO-BP, one of the most popular

63

congeners.6 In addition, 2OH-4MeO-BP can form several metabolic byproducts with

64

estrogenic activities, such as 2,2’OH-4MeO-BP and 2,4OH-BP.6 In addition, 2,4OH-BP

65

is speculated to be associated with endometriosis, an estrogen-dependent disease.10

66

Other benzophenone derivatives, such as 4-hydroxybenzophenone (4OH-BP) and


4

Page 5 of 32


67

2,2’,4,4’OH-BP, exhibited higher estrogenic activity than 2OH-4MeO-BP.11 Apart from

68

endocrine disrupting properties, BPs can also cause coral bleaching and disrupt gene

69

expression in zebrafish.12–14

70 71

Given their wide ranging physicochemical properties, BPs can be accommodated in

72

different environmental matrices (e.g. bulk water, suspended solids (SS), pore water

73

and sediments) in aquatic ecosystems.15–18 Previous studies have detected the

74

concentrations of BPs in surface water and sediments, with levels typically ranging from

75

ng L-1 to low µg L-1 for water samples and in the low ng g-1 range for sediments (dry

76

weight).2,7,19,20 In contrast, studies on the detection of BPs in SS and pore water are

77

limited.15,17 BPs associated with SS are expected to influence both the quality of the

78

water column (via sorption and desorption) and benthic sediments (via sedimentation

79

and resuspension).17,21 Sediment-pore water partitioning and diffusion across the

80

sediment-water column boundary are important processes that govern the transport,

81

fate and toxicity of BPs in aquatic systems.22,23 Since the fate of BPs in a surface water

82

body is linked to the fate and transport of particles (SS and sediments), it is essential to

83

study their occurrence concurrently in all relevant environmental compartments: bulk

84

water, SS, surficial benthic sediments and sediment pore water.

85 86

Thus, the primary objectives of this investigation were to quantify the concentrations of

87

seven targeted BP-type UV filters in a tropical urban watershed. BPs included were

88

2,4OH-BP, 2,2’,4,4’OH-BP, 2OH-4MeO-BP, 2,2’OH-4,4’MeO-BP, 2,2’OH’4MeO-BP,

89

4OH-BP and 4,4’-dihyroxybenzophenone (4DHB). BPs were quantified in the four


5


90

environmental compartments (dissolved in bulk water and sorbed to SS in the water

91

column and dissolved in pore water and sorbed to surficial sediments). The approach

92

was to investigate the temporal and spatial variations of the target BPs and to evaluate

93

the data with respect to sorption. Environmental risk assessment was performed to

94

assess the ecotoxicological risks posed by these BP-type UV filters. Results are useful

95

for assessing the environmental risk of BPs and elucidating their fate in aquatic

96

environments.

Page 6 of 32

97 98

2 Materials and methods

99 100

2.1 . Chemicals and reagents

101 102

The seven targeted BPs (i.e., 2,4OH-BP, 2,2’,4,4’OH-BP, 2OH-4MeO-BP, 2,2’OH-

103

4,4’MeO-BP, 2,2’OH’4MeO-BP, 4OH-BP and 4DHB) and benzophenone-d10 (BP-d10,

104

internal standard) of high purity grade (>99.9%) were purchased from Sigma-Aldrich

105

(Sigma-Aldrich, Singapore). Some environmentally important physicochemical

106

properties are given in Supporting Information (SI) Table S1. Individual stock solutions

107

(1000 mg L-1) were prepared in methanol from powder and stored in the dark at -20 ℃.

108

A mixture of all analytes was obtained by combining aliquots of the stock solutions.

109

Other chemical reagents and solvents, such as HPLC grade methanol, were of high

110

purity grade. Ultra-pure water was produced by a Milli-Q system (Sartorius, Singapore).

111


6

Page 7 of 32

112


2.2 . Sampling campaign

113 114

The watershed and sampling sites have been described elsewhere and are presented

115

in Figure S1.24–26 Briefly, the study area (about 10, 000 ha) is a tropical urban watershed

116

located in Singapore, accounting for about one-sixth of Singapore’s land area. The

117

watershed consists of a main water body (hereinafter “basin”), which receives the

118

discharge of five major tributaries. Water samples were collected in 1-L amber water

119

bottles at three sites (i.e., S1, S2 and S3) located in the basin: at 0.1 m (top), about 2.5

120

m (middle) and about 5 m below the water surface (near the bottom). At the 5 tributaries

121

(identified as SR, SC, RC, KR and GR), grab surface water samples were collected

122

(one sample per tributary). Surficial benthic sediment samples were collected at the

123

eight sampling sites from the top 10 cm with a stainless steel grabber. A total of 5

124

quarterly sampling events were conducted starting from December 2014 to December

125

2015. This was to capture the seasonal characteristics covering the northeast (NE)

126

monsoon (December-early March), inter-monsoon (late March-May, October-November)

127

and southwest (SW) monsoon (June-September) periods. All the samples were kept in

128

an ice-packed container during transport to the laboratory. The samples were stored in

129

a cold room (4 ℃) in the dark.

130 131

2.3 . Sample pre-treatment and extraction

132 133

BPs in the aqueous phases (i.e., bulk water and pore water) and solid matrices (i.e., SS

134

and sediments) were analyzed using a combination of solid phase extraction (SPE),


7


Page 8 of 32

135

ultrasound-assisted extraction and high-performance liquid chromatography coupled

136

with tandem mass spectrometry (HPLC-MS/MS). Detailed description about the

137

analytical procedures and method validation are described in the SI.

138 139

2.4 . Evaluation of distribution of benzophenones in dissolved and solid phases

140 141

The fraction of BPs associated with SS and sediments (ΦSS and ΦSed, %) was

142

calculated with the following equations:

143

= /( + ) ∗ 100%

(1)

144

= /( + ) ∗ 100%

(2)

145

where, , , and are the mass (in ng) of BPs in SS, bulk water,

146

sediments and pore water, respectively. Detailed derivations and calculation are

147

provided in the SI.

148 149

2.5 . Environmental risk assessment

150 151

Risk quotients (RQs) of BP-type UV filters were quantified with the ratio between the

152

measured environmental concentrations (MECs) in the dissolved phase (bulk water and

153

pore water) and the predicted no-effect concentrations (PNECs) (Equation (3)). The RQ

154

of a water sample (i.e., RQTotal) was defined as the sum of RQs of each BPs (RQi)

155

following the rule of concentration addition (Equation (4)).27,28

156

= /

157

!"#

= ∑%$&' $ = ∑%$&' $ /$

(3) (4)

158


8

Page 9 of 32


159

MEC values of BP-type UV filters were obtained from the present study. PNEC values

160

were derived from available ecotoxicological data with an assessment factor (Table S2).

161

The assessment factors were employed to compensate for the uncertainties in inter-

162

and intra-species variations, acute and chronic toxicity and the extrapolation of

163

laboratory data to the field.3,29 They were calculated following the European

164

Commission guidelines.30 To reflect the risk under the worst condition, the highest MEC

165

and the lowest PNEC of each BPs were employed in the risk assessment.7,28,29 RQ

166

based ranking criteria were applied to interpret the risk classification: “unlikely to pose

167

risk” for QR < 0.01; “low risk” for 0.01 < RQ

183

88%) and the basin samples (> 77.8%) (Table 1). In the tributaries, total BP

184

concentrations (∑ C ) were significantly higher (19-230.8 ng L-1) than the basin (20.4-

185

81 ng L-1) (Mann-Whitney test, p < 0.05), consistent with the tributaries being the main

186

source of BPs. Concentrations of 2,2’,4,4’OH-BP (0.8-109.2 ng L-1) and 2OH-4MeO-BP

187

(2.3-122.6 ng L-1) in tributaries varied the most. The high concentrations of the two BPs

188

may be a result of their wide application in sunscreen products (Table S3). Another

189

possibility may be due to their different application characteristics in commercial

190

products. For example, 2,2’,4,4’OH-BP, a congener commonly found in products more

191

related with daily life (e.g. nail polish, fragrance and shampoo), may have a higher

192

possibility of anthropogenic release (via sewage) than 2,4OH-BP, a congener which is

193

more related with products for beauty purposes (e.g. nail polish, nail treatment and

194

polish remover).31,32 In contrast to 2,2’,4,4’OH-BP and 2OH-4MeO-BP, concentration

195

levels of the other BP congeners (i.e., 2,4OH-BP, 2,2’OH-4MeO-BP, 4OH-BP and

196

4DHB) were relatively uniform as the highest detected concentration was less than 30

197

ng L-1. The discrepancy in concentration range was a result of peak values for selected

198

congeners for certain sampling events (Figure S2). Similar release events were

199

observed previously for some compounds (e.g. caffeine, bisphenol A and

200

perfluorononanoic acid) within this study area.26,33 These peak releases indicate that the

201

tributaries are subjected to variable contamination sources. As Singapore’s river-

202

reservoir systems are isolated from sewer systems, higher concentrations of BPs in

203

tributaries could possibly originate from other sources, such as leaking sewer pipelines


10

Page 11 of 32


204

and runoff from uncontrolled surface sites.7,20,25,26,34 These variable sources could

205

partially explain the wide concentration ranges observed in the tributaries.

206 207

Compared to the tributaries, the concentration ranges of the total BPs (20.4-81 ng L-1) in

208

the basin were smaller, likely due to mixing and dilution and the absence of point

209

sources that impact the basin. For individual compounds, only 2OH-4MeO-BP had a

210

relatively wide concentration range (4.5-56.1 ng L-1) while the remaining six BPs were

211

characterized by a smaller range, with a maximum level of 12.3 ng L-1 in the case of

212

2,2’,4,4’OH-BP. For each compound, the median levels in bulk waters from the basin

213

were 9.1-57.8% lower than that from the tributaries. In the basin water column,

214

concentration differences at the three layers were statistically insignificant (Figure 1A,

215

Mann-Whitney test, p > 0.05), indicating that the water in the basin was generally well

216

mixed.25,33

217 218

For a better comparison, the worldwide occurrence of various BP-type UV filters in fresh

219

surface water is summarized in Table S4 along with our results. Among all the members

220

of the BP family, 2OH-4MeO-BP is the most intensively studied congener worldwide

221

(Table S4). The measured 2OH-4MeO-BP concentrations in the present study were

222

generally lower than a previous study in the same study area.26 In addition, higher levels

223

(127-166 ng L-1) were also reported for 2OH-4MeO-BP in Bangkok, Thailand.7 The high

224

contamination levels may be correlated with high usage patterns of 2OH-4MeO-BP

225

containing products, such as sunscreens since our study area and Bangkok are both

226

located in tropical regions that prompt the use of sun-protecting lotions.4,35


11


Page 12 of 32

227 228

Total BPs concentration in pore water were 1.2 times higher than overlying water in

229

terms of median levels (Table 1, Table 2). The total BP concentration ranged from 48.3

230

to 115.1 ng L-1 with a median concentration of 63.5 ng L-1 (Table 2). The highest

231

concentrations (up to 40 ng L-1) were observed for 2,2’OH-4,4’MeO-BP and 4OH-BP,

232

while the lowest was for 4DHB (3.8 ng L-1). Based on median concentrations, the

233

predominant BPs were 4OH-BP (median concentration: 16.0 ng L-1), 2OH-4MeO-BP

234

(10.7 ng L-1) and 2,2’OH-4MeO-BP (10.5 ng L-1).

235 236

Since this is the first study reporting the concentration of BPs in pore water, no literature

237

data are available for comparison. We focused on the concentration differences

238

between overlying water and pore water, in order to understand the dynamic

239

interactions between the water column and the benthic layer. The median

240

concentrations of five BPs (i.e., 2,2’,4,4’OH-BP, 2OH-4MeO-BP, 2,2’OH-4,4’MeO-BP,

241

2,2’OH-4MeO-BP and 4OH-BP) were higher in pore water than in overlying water

242

(Figure 1A). This behavior is consistent with the hypothesis that SS have a higher

243

sorption capacity than bottom sediments, perhaps because of a higher surface area-to-

244

volume ratio in suspended particles when compared to sedimentary particles. Higher

245

levels of BPs in pore water may partially due to the hydrophobicity of these compounds,

246

coinciding with the fact that pore water in sediments is an organic-rich matrix.36–38 It

247

should be pointed out that a number of studies have suggested that pore water could be

248

a secondary contamination source for the overlying water column.39–41 Contrary to these

249

five BPs, the median concentration of 4DHB was higher in the overlying water than pore


12

Page 13 of 32


250

water (Figure 1A), suggesting that this chemical may be transported from overlying

251

water to pore water via diffusion. Similar observations have been reported elsewhere

252

(Table S5). Thus, it is difficult to ascertain the role of pore water in influencing the

253

overall environmental behavior of organic contaminants in water environments and

254

more effort is needed to further characterize the nature of sediments and the role

255

organic carbon may play in influencing contaminant flux.

256 257

3.2 . BPs in suspended solids and sediments

258 259

The total BP concentrations in SS ranged from 294.5 to 5813 ng g-1 d.w. in the

260

tributaries and more narrowly from 756.2 to 1834 ng g-1 d.w. in the basin (Table 1). The

261

detection frequencies in the SS of the tributaries ranged from 40% (2,4OH-BP) to 100%

262

for 2OH-4MeO-BP, 2,2’OH-4,4’MeO-BP, 4OH-BP and 4DHB. Concentrations of specific

263

BPs in SS ranged more widely in the in the tributaries than in the basin (Table 1). This

264

could be due to highly variable BP input and variable SS concentrations and

265

composition in the tributaries and attenuation due to dilution and mixing in the basin.

266

The total and median BP loads carried by the SS of the tributaries were significantly

267

lower than in the basin (Table 1, Mann-Whitney test, p < 0.05). This trend agrees with

268

the reduced BP concentrations in the bulk water samples, perhaps due to the stronger

269

sorption capacity of the basins SS (Table 1). This is possible because tributary flows

270

contain a higher content of poorly sorbing gravel and sand particles and a smaller

271

amount of phytoplankton (as indicated by chlorophyll, Table S6, Figure S5) when

272

compared to the basin.

273


13


Page 14 of 32

274

Sediments are often regarded as the final repository for hydrophobic organic

275

contaminants. In the benthic sediment samples, the concentration range (5.8-37 ng g-1

276

d.w.) and median level (13.7 ng g-1 d.w.) of total BPs were much lower when compared

277

to SS (Table 1, Table 2). The highest concentrations were measured for 4OH-BP (9.3

278

ng g-1 d.w.) and 4DHB (9.1 ng g-1 d.w.). Some of the congeners, such as 2,4OH-BP,

279

2OH-4MeO-BP and 2,2’OH-4,4’MeO-BP, were measured to be less than 4 ng g-1 d.w.

280

The concentrations of the seven BPs in the tributary sediments were comparable to that

281

in the basin sediments (Mann-Whitney test, p > 0.05). Compared to bulk water, less

282

attention has been paid to BPs in sediments and 2OH-4MeO-BP again was the most

283

commonly studied congener in the BP family (Table S7). 2OH-4MeO-BP levels in the

284

present study were comparable to levels found in China (0.16-1.07 ng g-1 d.w.), USA

285

(0.73-4.66 ng g-1 d.w.) and Chile (n.d.-2.96 ng g-1 d.w.). In contrast, sediments in some

286

other countries (i.e., South Korea, Japan and Germany) were less contaminated by

287

2OH-4MeO-BP compared to our study. Aside from 2OH-4MeO-BP, other BP derivatives

288

were also detected in sediments (Table S7), with relatively higher concentrations

289

detected in the present study potentially due to the high local usage of sunscreens.

290 291

Like BPs in dissolved phase, concentrations of BPs in SS collected from three different

292

layers and benthic sediments are shown in Figure 1B. Unlike overlying water, the

293

deeper particles in the water column tended to have less BPs than surface particles and

294

the contamination levels of BPs in sediments were minimal when compared to SS. This

295

may imply that the SS release the loaded BPs as they settle. Reduced sorption capacity

296

could be one possible explanation for the reduction in BPs loading. It is generally


14

Page 15 of 32


297

accepted that particles with bigger size tend to reside lower in the water column.42,43 As

298

particles further reach the benthic sediment layer, they may also tend to aggregate to

299

form bigger particles such as larger sand and gravel. Thus, the surface area-to-volume

300

ratio of the particles will tend to decrease vertically, leading to a lower sorption capacity.

301

In addition, similar to the observation from tributaries and the basin, the differences in

302

particle compositions in different layers may also lead to varying sorption capacities. To

303

be specific, particles in the upper layer generally contain more phytoplankton

304

(chlorophyll concentration in Table S6, Figure S5), which is lipid-rich in nature, resulting

305

in a higher sorption capacity.44 The second possibility is that BPs in the sediment phase

306

may undergo biodegradation processes which result in the lower concentration of BPs

307

in sediments than that in SS. For example, 2OH-4MeO-BP was proven to be

308

enzymatically transformed to 2,4OH-BP and 2,2’OH-4MeO-BP.45 In addition, the

309

biodegradation of 2OH-4MeO-BP is more favorable under anoxic conditions (half-life:

310

4.2 d) than oxic conditions (half-life: 10.7 d), where the former is more likely to occur at

311

lower depths.46

312 313

3.3 . Temporal pattern

314 315

The seasonal influence of Singapore’s tropical rainforest climate (NE and SW monsoon

316

separated by inter-monsoon seasons) on the occurrence of BPs in the watershed was

317

examined in Table S8, where the median concentrations and the ranges of the seven

318

BPs are presented. The distribution of the seven BPs in the four phases was highly

319

variable, indicating that the seasonal effect (especially rainfall) on the occurrence of this


15


Page 16 of 32

320

group of chemicals is negligible. This agrees with a previous report that Singapore’s

321

tropical climate (e.g. uniform temperatures and abundant rainfall) did not affect the

322

occurrence of selected personal care products (PPCPs). However, seasonal differences

323

were reported for UV filters elsewhere, typically those with significant seasonal

324

temperature variations (e.g. Korea).47,48 In these studies, the observed seasonal

325

variations may manifest the anthropogenic sources of these chemicals, such as the use

326

of sunscreens and other personal care products during the summer period. It is noted

327

that Singapore is a tropical country and therefore, application of sunscreen would likely

328

be year-round.

329 330

3.4 . Solid-solution distribution of BPs in the water column and sediments

331 332

To further understand the behavior of BPs in the water column and bottom sediment,

333

the distribution of individual BPs between dissolved and particulate phases both in the

334

water column and bottom sediment phase was calculated based on paired

335

concentrations over the entire sampling period (Figure 2). In the water column, 2,4OH-

336

BP and 4DHB were predominately detected in bulk water, accounting for 74.8% and 89%

337

of the total mass, respectively. The remaining five BPs distributed almost uniformly (45-

338

59%) in the two phases in the water column (bulk water and SS). However, the

339

distribution pattern was different in the sediment layer where a major proportion of the

340

target BPs (> 58%) was detected in pore water. The obtained percentages agreed with

341

a previous observation that PPCPs can be predominantly detected whether in dissolved

342

phase or solid phase.49 Hence, routine monitoring campaigns may underestimate the


16

Page 17 of 32


343

actual contamination levels in water samples (with filtration) and overestimate sediment-

344

bound contaminant levels (without pore water separation).

345 346

3.5 . Environmental risk assessment

347 348

A preliminary environmental risk assessment was conducted to identify the

349

ecotoxicological potential of BPs to the aquatic organisms in the worst-case scenario,

350

i.e., highest detected concentrations (Table 3). In bulk water, 2OH-4MeO-BP posed a

351

medium risk to the organisms and 2,2’,4,4’OH-BP posed a low risk. The remaining BPs

352

were unlikely to pose risk to organisms reside in the water column. It is noteworthy that

353

the obtained RQs of 2OH-4MeO-BP and 2,2’,4,4’OH-BP were a result of intermittent

354

peak values (Figure S2). These peaks values greatly dedicated the overall medium risk

355

caused by the seven BPs in the bulk water (RQTotal = 0.52). Similarly, with an RQTotal of

356

0.11, BPs posed a medium risk to benthic organisms, which is mainly contributed by

357

2OH-4MeO-BP (RQ = 0.09, low risk). The remaining six BPs in pore water were unlikely

358

to trigger risk to benthic organisms.

359 360

Various studies have evaluated the ecotoxicological risks of BPs using the RQ method.

361

However, risk data pertaining to tropical regions was limited. Compared to our results,

362

Fent et al (2010a) reported a lower RQ of 0.07 (low risk) for 2OH-4MeO-BP based on

363

ecotoxicological data on chronic effects in fish, as well as acute effects in Daphnia

364

magna. Similarly, 2OH-4MeO-BP was reported to have a small potential to pose

365

adverse effects in Spain.51 However, this compound may pose significant risks as


17


Page 18 of 32

366

indicated previously 52. As for other types of BPs, 2,4OH-BP was previously reported to

367

be unlikely to pose any risk, agreeing with our results.53 The same study revealed that

368

2,2’,4,4’OH-BP posed no risk.53

369 370

To the best of our knowledge, this is one of first studies conducting the risk assessment

371

for four types of BPs (i.e., 2,2’OH-4,4’MeO-BP, 2,2’OH-4MeO-BP, 4OH-BP and 4DHB).

372

In addition, we reported the accumulative risk (RQTotal) of several types of BPs for the

373

first time. The RQTotal was calculated assuming additive interaction.50 The evaluation of

374

the total risk posed by various BP-type UV filters is practically important as these

375

chemicals generally occur in mixtures. However, it is worth mentioning that the risk

376

assessment here was conducted based on limited ecotoxicological data (e.g. only one

377

datum for 2,2’,4,4’OH-BP, 2,2’OH-4,4’MeO-BP, 2,2’OH-4MeO-BP and 4DHB).

378

Therefore, more studies regarding the toxicity of single and mixture BP-type UV filters

379

are needed for a better understanding of the actual risk of BP-type UV filters.

380 381

Supporting information

382 383

This supporting information contains additional information on sampling map, sample

384

process, instrumental analysis, quality assurance and quality control, detailed derivation

385

and calculation, structure and physicochemical properties of BP-type UV filters, reported

386

ecotoxicological data on BP-type UV filters, literature data on occurrence of various

387

organic contaminants, concentrations of BP-type UV filters, water quality data, and SS


18

Page 19 of 32


388

on filters in the present study. It is available free of charge on the ACS Publication at

389

http: //pubs.acs.org.

390 391

Author information

392 393

Corresponding Author: *Tel.: +65 65168104; E-mail address: [email protected] (K.

394

Y-H. Gin)

395 396

Note

397 398

The authors declare no competing financial interest.

399 400

Acknowledgments

401 402

This research/project is supported by the National Research Foundation, Prime

403

Minister’s Office, Singapore under its Campus for Research Excellence and

404

Technological Enterprise (CREATE) programme and the Singapore Ministry Education

405

Academic Research Fund R-302-000-088-750. Financial support was also provided by

406

the China Scholarship Council (CSC) and National University of Singapore (NUS). We

407

are grateful to PUB, Singapore's national water agency for providing logistical support in

408

this study.

409


19


410

Page 20 of 32

References

411 412

(1)

Jeon, H.-K.; Chung, Y.; Ryu, J.-C. Simultaneous determination of benzophenone-

413

type UV filters in water and soil by gas chromatography–mass spectrometry. J.

414

Chromatogr. A 2006, 1131 (1), 192–202.

415

(2)

Zhang, Z.; Ren, N.; Li, Y.-F.; Kunisue, T.; Gao, D.; Kannan, K. Determination of

416

benzotriazole and benzophenone UV filters in sediment and sewage sludge.

417

Environ. Sci. Technol. 2011, 45 (9), 3909–3916.

418

(3)

Tsui, M. M. P.; Lam, J. C. W.; Ng, T. Y.; Ang, P. O.; Murphy, M. B.; Lam, P. K.-S.

419

Occurrence, distribution and fate of organic UV filters in coral communities.

420

Environ. Sci. Technol. 2017, 51 (8), 4182–4190.

421

(4)

Sánchez-Quiles, D.; Tovar-Sánchez, A. Are sunscreens a new environmental risk associated with coastal tourism? Environ. Int. 2015, 83, 158–170.

422 423

(5)

Shaath, N. A. The encyclopedia of ultraviolet filters; Allured Pub., 2007.

424

(6)

Kim, S.; Choi, K. Occurrences, toxicities, and ecological risks of benzophenone-3,

425

a common component of organic sunscreen products: a mini-review. Environ. Int.

426

2014, 70, 143–157.

427

(7)

Tsui, M. M. P.; Leung, H. W.; Wai, T.-C.; Yamashita, N.; Taniyasu, S.; Liu, W.;

428

Lam, P. K. S.; Murphy, M. B. Occurrence, distribution and ecological risk

429

assessment of multiple classes of UV filters in surface waters from different

430

countries. Water Res. 2014, 67, 55–65.

431 432

(8)

Ozáez, I.; Martínez-Guitarte, J. L.; Morcillo, G. The UV filter benzophenone 3 (BP3) activates hormonal genes mimicking the action of ecdysone and alters embryo


20

Page 21 of 32


433

development in the insect Chironomus riparius (Diptera). Environ. Pollut. 2014,

434

192, 19–26.

435

(9)

Suzuki, T.; Kitamura, S.; Khota, R.; Sugihara, K.; Fujimoto, N.; Ohta, S.

436

Estrogenic and antiandrogenic activities of 17 benzophenone derivatives used as

437

UV stabilizers and sunscreens. Toxicol. Appl. Pharmacol. 2005, 203 (1), 9–17.

438

(10) Kunisue, T.; Chen, Z.; Buck Louis, G. M.; Sundaram, R.; Hediger, M. L.; Sun, L.;

439

Kannan, K. Urinary concentrations of benzophenone-type UV filters in US women

440

and their association with endometriosis. Environ. Sci. Technol. 2012, 46 (8),

441

4624–4632.

442

(11) Kawamura, Y.; Ogawa, Y.; Nishimura, T.; Kikuchi, Y.; Nishikawa, J.; Nishihara, T.;

443

Tanamoto, K. Estrogenic activities of UV stabilizers used in food contact plastics

444

and benzophenone derivatives tested by the yeast two-hybrid assay. J. Heal. Sci.

445

2003, 49 (3), 205–212.

446

(12) Blüthgen, N.; Zucchi, S.; Fent, K. Effects of the UV filter benzophenone-3

447

(oxybenzone) at low concentrations in zebrafish (Danio rerio). Toxicol. Appl.

448

Pharmacol. 2012, 263 (2), 184–194.

449

(13) Downs, C. A.; Kramarsky-Winter, E.; Segal, R.; Fauth, J.; Knutson, S.; Bronstein,

450

O.; Ciner, F.; Jeger, R.; Lichtenfeld, Y.; Woodley, C.; et al. Toxicopathological

451

Effects of the Sunscreen UV Filter, Oxybenzone (Benzophenone-3), on Coral

452

Planulae and Cultured Primary Cells and Its Environmental Contamination in

453

Hawaii and the U.S. Virgin Islands. Arch. Environ. Contam. Toxicol. 2016, 70 (2),

454

265–288.

455

(14) Downs, C. A.; Kramarsky-Winter, E.; Fauth, J. E.; Segal, R.; Bronstein, O.; Jeger,


21


Page 22 of 32

456

R.; Lichtenfeld, Y.; Woodley, C. M.; Pennington, P.; Kushmaro, A. Toxicological

457

effects of the sunscreen UV filter, benzophenone-2, on planulae and in vitro cells

458

of the coral, Stylophora pistillata. Ecotoxicology 2014, 23 (2), 175–191.

459

(15) Benedé, J. L.; Chisvert, A.; Salvador, A.; Sánchez-Quiles, D.; Tovar-Sánchez, A.

460

Determination of UV filters in both soluble and particulate fractions of seawaters

461

by dispersive liquid–liquid microextraction followed by gas chromatography–mass

462

spectrometry. Anal. Chim. Acta 2014, 812, 50–58.

463

(16) Turner, A.; Millward, G. E. Suspended particles: their role in estuarine

464

biogeochemical cycles. Estuar. Coast. Shelf Sci. 2002, 55 (6), 857–883.

465

(17) Li, Y.; Liu, B.; Zhang, X.; Wang, J.; Gao, S. The distribution of veterinary

466

antibiotics in the river system in a livestock-producing region and interactions

467

between different phases. Environ. Sci. Pollut. Res. 2016, 23 (16), 16542–16551.

468

(18) Lara-Martín, P. A.; Renfro, A. A.; Cochran, J. K.; Brownawell, B. J.

469

Geochronologies of pharmaceuticals in a sewage-impacted estuarine urban

470

setting (Jamaica Bay, New York). Environ. Sci. Technol. 2015, 49 (10), 5948–

471

5955.

472

(19) Rodil, R.; Moeder, M. Development of a method for the determination of UV filters

473

in water samples using stir bar sorptive extraction and thermal desorption–gas

474

chromatography–mass spectrometry. J. Chromatogr. A 2008, 1179 (2), 81–88.

475

(20) Jurado, A.; Gago-Ferrero, P.; Vàzquez-Suñé, E.; Carrera, J.; Pujades, E.; Díaz-

476

Cruz, M. S.; Barceló, D. Urban groundwater contamination by residues of UV

477

filters. J. Hazard. Mater. 2014, 271, 141–149.

478

(21) He, Q.-S.; Wang, Q.-M.; Wang, Y.; He, W.; Qin, N.; Kong, X.-Z.; Liu, W.-X.; Yang,


22

Page 23 of 32


479

B.; Xu, F.-L. Temporal and spatial variations of organochlorine pesticides in the

480

suspended particulate matter from Lake Chaohu, China. Ecol. Eng. 2015, 80,

481

214–222.

482

(22) ter Laak, T. L.; Agbo, S. O.; Barendregt, A.; Hermens, J. L. M. Freely dissolved

483

concentrations of PAHs in soil pore water: Measurements via solid-phase

484

extraction and consequences for soil tests. Environ. Sci. Technol. 2006, 40 (4),

485

1307–1313.

486

(23) Yu, Y.; Xu, J.; Wang, P.; Sun, H.; Dai, S. Sediment-porewater partition of

487

polycyclic aromatic hydrocarbons (PAHs) from Lanzhou Reach of Yellow River,

488

China. J. Hazard. Mater. 2009, 165 (1), 494–500.

489

(24) Nguyen, V. T.; Reinhard, M.; Karina, G. Y.-H. Occurrence and source

490

characterization of perfluorochemicals in an urban watershed. Chemosphere

491

2011, 82 (9), 1277–1285.

492

(25) Nguyen, V. T.; Gin, K. Y.-H.; Reinhard, M.; Liu, C. Occurrence, fate, and fluxes of

493

perfluorochemicals (PFCs) in an urban catchment: Marina Reservoir, Singapore.

494

Water Sci. Technol. 2012, 66 (11), 2439–2446.

495

(26) You, L.; Nguyen, V. T.; Pal, A.; Chen, H.; He, Y.; Reinhard, M.; Gin, K. Y.-H.

496

Investigation of pharmaceuticals, personal care products and endocrine disrupting

497

chemicals in a tropical urban catchment and the influence of environmental

498

factors. Sci. Total Environ. 2015, 536, 955–963.

499

(27) Hernando, M.; Mezcua, M.; Fernández-Alba, A. R.; Barceló, D. Environmental risk

500

assessment of pharmaceutical residues in wastewater effluents, surface waters

501

and sediments. Talanta 2006, 69 (2), 334–342.


23


Page 24 of 32

502

(28) Tsui, M. M. P.; Leung, H. W.; Lam, P. K. S.; Murphy, M. B. Seasonal occurrence,

503

removal efficiencies and preliminary risk assessment of multiple classes of

504

organic UV filters in wastewater treatment plants. Water Res. 2014, 53, 58–67.

505

(29) Lai, W. W.-P.; Lin, Y.-C.; Tung, H.-H.; Lo, S.-L.; Lin, A. Y.-C. Occurrence of

506

pharmaceuticals and perfluorinated compounds and evaluation of the availability

507

of reclaimed water in Kinmen. Emerg. Contam. 2016, 2 (3), 135–144.

508

(30) European Commission. Technical Guidance Document in Support of Commission

509

Directive 93/67/EEC on Risk Assessment for New Notified Substances and

510

Commission Regulation (EC) N. 1488/94 on Risk Assessment for Existing

511

Substances; Office for official publications of the European communities, 1996.

512

(31) Environmental Working Group. EWG’s skin deep cosmetic database:

513

Benzophenone-2

514

https://www.ewg.org/skindeep/ingredient/700687/BENZOPHENONE-

515

2/#.WmxBGK6WaUk (accessed Jan 27, 2018).

516

(32) Environmental Working Group. EWG’s skin deep cosmetic database:

517

Benzophenone-1

518

https://www.ewg.org/skindeep/ingredient/700685/BENZOPHENONE-

519

1/#.Wmw27K6WaUk (accessed Jan 27, 2018).

520

(33) Chen, H.; Reinhard, M.; Nguyen, T. V.; You, L.; He, Y.; Gin, K. Y.-H.

521

Characterization of occurrence, sources and sinks of perfluoroalkyl and

522

polyfluoroalkyl substances (PFASs) in a tropical urban catchment. Environ. Pollut.

523

2017, 227, 397–405.

524

(34) Tran, N. H.; Li, J.; Hu, J.; Ong, S. L. Occurrence and suitability of pharmaceuticals


24

Page 25 of 32


525

and personal care products as molecular markers for raw wastewater

526

contamination in surface water and groundwater. Environ. Sci. Pollut. Res. 2014,

527

21 (6), 4727–4740.

528

(35) Barón, E.; Gago-Ferrero, P.; Gorga, M.; Rudolph, I.; Mendoza, G.; Zapata, A. M.;

529

Díaz-Cruz, S.; Barra, R.; Ocampo-Duque, W.; Páez, M. Occurrence of

530

hydrophobic organic pollutants (BFRs and UV-filters) in sediments from South

531

America. Chemosphere 2013, 92 (3), 309–316.

532

(36) Zhou, J. L.; Hong, H.; Zhang, Z.; Maskaoui, K.; Chen, W. Multi-phase distribution

533

of organic micropollutants in Xiamen Harbour, China. Water Res. 2000, 34 (7),

534

2132–2150.

535

(37) Maskaoui, K.; Zhou, J. L.; Hong, H. S.; Zhang, Z. L. Contamination by polycyclic

536

aromatic hydrocarbons in the Jiulong River estuary and Western Xiamen Sea,

537

China. Environ. Pollut. 2002, 118 (1), 109–122.

538

(38) Yu, Y.; Xu, J.; Sun, H.; Dai, S. Sediment–porewater partition of nonylphenol

539

polyethoxylates: field measurements from Lanzhou Reach of Yellow River, China.

540

Arch. Environ. Contam. Toxicol. 2008, 55 (2), 173–179.

541

(39) Xu, J.; Zhang, Y.; Zhou, C.; Guo, C.; Wang, D.; Du, P.; Luo, Y.; Wan, J.; Meng, W.

542

Distribution, sources and composition of antibiotics in sediment, overlying water

543

and pore water from Taihu Lake, China. Sci. Total Environ. 2014, 497, 267–273.

544

(40) Alvarez, D. A.; Rosen, M. R.; Perkins, S. D.; Cranor, W. L.; Schroeder, V. L.;

545

Jones-Lepp, T. L. Bottom sediment as a source of organic contaminants in Lake

546

Mead, Nevada, USA. Chemosphere 2012, 88 (5), 605–611.

547

(41) Guo, J.; Li, Z.; Ranasinghe, P.; Bonina, S.; Hosseini, S.; Corcoran, M. B.; Smalley,


25


548

C.; Kaliappan, R.; Wu, Y.; Chen, D. Occurrence of atrazine and related

549

compounds in sediments of upper Great Lakes. Environ. Sci. Technol 2016, 50

550

(14), 7335–7343.

551 552 553 554 555

Page 26 of 32

(42) Chapman, D. V; Organization, W. H. Water quality assessments: a guide to the use of biota, sediments and water in environmental monitoring. 1996. (43) Yano, S. In-Situ Measurement of Mercury Transport in the Sea Water of Minamata Bay. Procedia Earth Planet. Sci. 2013, 6, 448–456. (44) Maes, H. M.; Maletz, S. X.; Ratte, H. T.; Hollender, J.; Schaeffer, A. Uptake,

556

Elimination, and Biotransformation of 17α-Ethinylestradiol by the Freshwater Alga

557

Desmodesmus subspicatus. Environ. Sci. Technol. 2014, 48 (20), 12354–12361.

558

(45) Nakagawa, Y.; Suzuki, T. Metabolism of 2-hydroxy-4-methoxybenzophenone in

559

isolated rat hepatocytes and xenoestrogenic effects of its metabolites on MCF-7

560

human breast cancer cells. Chem. Biol. Interact. 2002, 139 (2), 115–128.

561

(46) Liu, Y.; Ying, G.; Shareef, A.; Kookana, R. S. Biodegradation of the ultraviolet

562

filter benzophenone‐3 under different redox conditions. Environ. Toxicol. Chem.

563

2012, 31 (2), 289–295.

564

(47) Ekpeghere, K. I.; Kim, U.-J.; Sung-Hee, O.; Kim, H.-Y.; Oh, J.-E. Distribution and

565

seasonal occurrence of UV filters in rivers and wastewater treatment plants in

566

Korea. Sci. Total Environ. 2016, 542, 121–128.

567

(48) Kim, K. Y.; Ekpeghere, K. I.; Jeong, H.-J.; Oh, J.-E. Effects of the summer holiday

568

season on UV filter and illicit drug concentrations in the Korean wastewater

569

system and aquatic environment. Environ. Pollut. 2017, 227, 587–595.

570

(49) da Silva, B. F.; Jelic, A.; López-Serna, R.; Mozeto, A. A.; Petrovic, M.; Barceló, D.


26

Page 27 of 32


571

Occurrence and distribution of pharmaceuticals in surface water, suspended

572

solids and sediments of the Ebro river basin, Spain. Chemosphere 2011, 85 (8),

573

1331–1339.

574

(50) Fent, K.; Kunz, P. Y.; Zenker, A.; Rapp, M. A tentative environmental risk

575

assessment of the UV-filters 3-(4-methylbenzylidene-camphor), 2-ethyl-hexyl-4-

576

trimethoxycinnamate, benzophenone-3, benzophenone-4 and 3-benzylidene

577

camphor. Mar. Environ. Res. 2010, 69, S4–S6.

578

(51) Rodríguez, A. S.; Sanz, M. R.; Rodríguez, J. R. B. Occurrence of eight UV filters

579

in beaches of Gran Canaria (Canary Islands). An approach to environmental risk

580

assessment. Chemosphere 2015, 131, 85–90.

581

(52) Sang, Z.; Leung, K. S. Y. Environmental occurrence and ecological risk

582

assessment of organic UV filters in marine organisms from Hong Kong coastal

583

waters. Sci. Total Environ. 2016, 566–567, 489–498.

584

(53) Fent, K.; Kunz, P. Y.; Gomez, E. UV filters in the aquatic environment induce

585

hormonal effects and affect fertility and reproduction in fish. Chim. Int. J. Chem.

586

2008, 62 (5), 368–375.

587


27


588 589

590 591 592

Page 28 of 32

Table 1. Detection frequency, median and range of BP concentrations in bulk water and suspended solids from the tributaries and the basin Compounds Tributary Basin Ratiob DF (%) Range Median DF (%) Range Median -1 Bulk water (ng L ) Total BPsa 19.0-230.8 45.2 20.4-81.0 28.7 1.57 2,4OH-BP 100.0% 1.0-18.2 5.4 100.0% 1.4-5.2 3.2 1.69 2,2’,4,4’OH-BP 100.0% 0.8-109.2 7.9 100.0% 1.6-12.3 3.3 2.39 2OH-4MeO-BP 100.0% 2.3-122.6 8.4 100.0% 4.5-56.1 6.9 1.22 2,2’OH-4,4’MeO-BP 96.0%

Occurrence and fate of benzophenone-type UV ... - ACS Publications

Recommend Documents