Alkylphenols affect lobster (Homarus americanus) larval survival, molting and metamorphosis

Abstract

Alkylphenols are widely distributed in the marine environment and we have found them to be widely dispersed in New England lobster populations. In vertebrates, these compounds act as estrogenic endocrine disruptors. Here, we tested two alkylphenols, bisphenol A and 2,4-bis-(dimethylbenzyl)phenol for their effects on lobster larvae. In particular, we examined their toxicity and their effects on molting and metamorphosis. Lobsters were raised to stage 2 and were then isolated individually in ice cube trays with nylon mesh netting on the bottom giving access to flow through cooled seawater. The experimental larvae were fed with 5 or 10 ng alkylphenol per day in their diet. Controls were fed the same diet minus the test chemicals. The alkylphenols were toxic to second and third stage larvae, and fourth stage post-larvae, with 13-21% surviving to 25 days compared to 69% of controls. The compounds significantly delayed each molt by 2-3.5 days, and the surviving treated larvae were predominantly larval-juvenile intermediates at metamorphosis (62%). The differences between treatments and controls in all cases were highly significant using survival analysis based on the Weibull distribution. We conclude that alkylphenols are endocrine disruptors to lobster larvae at metamorphosis because they possess juvenile hormone activity. They also delay molting, reduce growth, and are toxic at relatively low concentrations.

High‐frequency sampling and piecewise models reshape dispersal kernels of a common reef coral

“…, ; crustacean, Laufer et al. ). However, for both the survival and competence dynamics, the exponential, Weibull and generalized Weibull models were unable to characterize important qualitative features of larval dynamics, with important consequences for modeling larval dispersal.…”

Endocrine-Disrupting Alkylphenols are Widespread in the Blood of Lobsters from Southern New England and Adjacent Offshore Areas

“…Lobsters in this region are likely repeatedly exposed to these endocrine-disrupting compounds throughout the course of their lifetime. We do not understand all the ways in which these compounds affect the biology of lobsters, but have good reason for concern: Exposure to very low levels of alkylphenols disrupted metamorphosis significantly and was severely toxic for larval lobsters (Laufer et al 2012a), and weakened cuticles of adult lobsters (Laufer et al 2012b). Earlier work on other crustaceans (Forward & Costlow 1976, Costlow 1977, Abdu et al 1998) and mosquitoes (Sacher 1971) also suggests that alkylphenols may disrupt behavior, metamorphosis, and cuticle hardening of lobsters and related organisms.…”

“…Endocrine-disrupting activity on lobsters has been demonstrated for compound 3 and the related alkylphenol bispheno A. Larval lobsters exposed to 5 ng/day or 10 ng/day of alkylphenols in their diets experienced abnormal metamorphosis, as well as reduced survival and delay of metamorphosis (Laufer et al 2012a). Compound 2 has been shown to disrupt sclerotization and metamorphosis of mosquito larvae, even at relatively low (0.1 ppm) doses (Sacher 1971, Zomer & Lipke 1981, Semensi & Sugumaran 1986).…”

“…Alkylphenols are vertebrate and inve/rtebrate estrogenic endocrine disruptors (Biggers & Laufer 2004, Laufer et al 2012a widely used in the production of alkylphenol ethoxylates, which are used in industrial and household detergents, surfactants, paints, wetting agents, wood pulping, textile manufacture, plastic manufacture, petroleum recovery, and phenolic resins; as antioxidants, polymer stabilizers, and curing agents; and in many other products (Naylor et al 1992, Naylor 1995, Ying et al 2002, Soares et al 2008. Worldwide annual alkylphenol production was estimated to be 500,000 t and increasing in 1997 (Ying 2006), and a large proportion of this material ends up in aquatic or marine environments via discharge from wastewater treatment plants or industry (Soares et al 2008, David et al 2009, Harman et al 2011.…”

Long Island Sound

“…A wide range of substances has potential to disrupt endocrine systems of organisms, with consequences including changes in sex ratios and general decline in population health and viability Laufer and Baclaski 2012). Broad classes of substances can act as EDCs and mimic hormones in estuarine organisms.…”