Subscriber access provided by University of Otago Library
Article
Effects of Exposure to WwTW Effluents over Two Generations on Sexual Development and Breeding in Roach Rutilus rutilus Patrick Birungi Hamilton, Anke Lange, Elizabeth Nicol, Lisa K Bickley, Eliane De-Bastos, Susan Jobling, and Charles Tyler Environ. Sci. Technol., Just Accepted Manuscript • DOI: 10.1021/acs.est.5b03777 • Publication Date (Web): 06 Oct 2015 Downloaded from http://pubs.acs.org on October 10, 2015
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 free 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 accessible to all readers and 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.
Environmental Science & Technology 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
Effects of Exposure to WwTW Effluents over
2
Two Generations on Sexual Development and
3
Breeding in Roach Rutilus rutilus
4 5
Patrick B. Hamilton,* † Anke Lange,† Elizabeth Nicol,‡ Lisa K. Bickley,† Eliane SR De-
6
Bastos,† Susan Jobling. ‡ Charles R. Tyler†
7 8
†
University of Exeter, Biosciences, College of Life and Environmental Sciences, Exeter,
9 10
EX4 4QD, UK ‡
Institute of Environment, Health and Societies, Brunel University, Uxbridge, Middlesex,
11
UB8 3PH, UK
12 13 14 15 16
Word count: currently 5462 + 1200 (2 figures at 300 word equivalents and 1 figure at 600 word equivalents each) = 6662
17
1 ACS Paragon Plus Environment
Environmental Science & Technology
18
ABSTRACT
19 20
Exposure to environmental estrogens in wastewater treatment works (WwTW) effluents
21
induces feminized responses in male fish, including the development of eggs in male
22
testes. However, the impacts on the offspring of exposed fish are not well understood. In
23
this study we examined whether roach (Rutilus rutilus) from mothers that had been
24
exposed to an undiluted WwTW effluent from early life to sexual maturity had altered
25
susceptibility to gonadal feminization and an impaired capacity to reproduce. For males
26
from both WwTW effluent exposed mothers and dilution water exposed mothers, effluent
27
exposure for up to three years and nine months induced feminized male gonads, although
28
the intersex condition was relatively mild. There was no difference in the severity of
29
gonadal feminization in roach derived from either WwTW effluent exposed or dilution
30
water exposed mothers. Furthermore, a breeding study revealed that roach with effluent-
31
exposed mothers reproduced with an equal success as roach with mothers exposed to
32
clean water. Roach exposed to the effluent for three years in this study were able to
33
reproduce successfully. Our findings provide no evidence for impacts of WwTW effluent
34
exposure on reproduction or gonadal disruption in roach down the female germ line and
35
add to existing evidence that male roach with a mild intersex condition are able to breed
36
competitively.
37
38 39
INTRODUCTION
2 ACS Paragon Plus Environment
Page 2 of 32
Page 3 of 32
Environmental Science & Technology
40
Wastewater treatment work (WwTW) effluents contain tens of thousands of chemicals,
41
including natural and pharmaceutical steroid estrogens. There is substantial evidence that
42
exposure of male fish to WwTW effluents causes feminization, and that severely
43
feminized male gonads impair breeding success of those individuals.1-3 Feminized male
44
phenotypes include the production of the female yolk protein precursor vitellogenin,4
45
feminized reproductive ducts and the presence of both male and female germ cells in the
46
male gonad.5
47 48
The estrogenic activity of WwTW effluents predominantly results from the presence of
49
steroid estrogens emanating from human excretion. These include estradiol (E2), its
50
breakdown product, estrone (E1) and the pharmaceutical estrogen 17α-ethinylestradiol
51
(EE2), a component of the female contraceptive pill.6 Other substances detected in
52
effluents shown to be estrogenic include the pharmaceutical metformin,7 alkylphenoxy
53
polyethoxylates (APEOs) and their breakdown products,8 and plasticizers (e.g. bisphenol
54
A9). These chemicals may also contribute to the feminization of male fish in some rivers
55
receiving high level industry discharges. Natural plant estrogens occur widely in effluent
56
discharges,10 but they are relatively weak in potency compared with steroidal estrogens.11
57
There is also some evidence supporting the involvement of chemicals that can act as
58
antiandrogens contribute to the feminization of fish in some rivers.6, 12-18
59
In the United Kingdom, concern regarding the impacts of estrogenic effluents on fish
60
health and fish populations led to a £40M investment to evaluate the ability of various
61
secondary and tertiary treatment processes to remove estrogens from effluents
62
more recently a £100M chemical investigation programme. From this work it has been
3 ACS Paragon Plus Environment
19, 20
and
Environmental Science & Technology
Page 4 of 32
63
established that although some tertiary processes, such as activated carbon are highly
64
effective, they are expensive and incur a greater carbon footprint than more widely
65
adopted secondary treatment processes.19, 21
66 67
Much of the current knowledge on the impacts of treated estrogenic effluents is derived
68
from studies on the cyprinid fish roach (Rutilus rutilus), which commonly occurs in
69
sewage-contaminated rivers in the United Kingdom. Endocrine disruption in fish was
70
first reported when a low (5%) incidence of intersex was found in wild roach populations
71
living just downstream of a WwTW effluent discharge into the River Lee in the UK.22
72
Later surveys found roach with feminized gonads at 86% of UK river locations
73
surveyed.23, 24. All feminized phenotypes seen in wild roach have been induced through
74
controlled exposures to WwTW discharges
75
female germ cells in an otherwise male gonad requiring persistent exposure during the
76
period of gonadal differentiation.
19, 25, 26
and to EE2,27,
28
with induction of
77 78
A major concern is whether WwTW effluents impact on fish populations by affecting
79
reproductive output. Several experimental exposures to EE2, at concentrations that have
80
been measured occasionally in WwTW effluents and encompassing the period of sexual
81
development, have found that exposure can result in complete feminization and/or
82
reproductive failure.28-32 Notably, exposure of an entire lake in Canada for three years to
83
4-6 ng EE2/L resulted in the collapse of the fathead minnow (Pimephales promelas)
84
population residing in this lake.31 These exposures, however, exceed typical river
85
concentrations of estrogens.33 Nevertheless EE2 exposures at concentrations
