Trans-generation study of the effects of nonylphenol ethoxylate on the reproduction of the snail Biomphalaria tenagophila

Abstract

Nonylphenols ethoxylates (NPEs) are surfactants used in a variety of products. They are found in domestic sewage, industrial effluents and as contaminants in water bodies. This study was undertaken to evaluate the effects of NPE with 9.5 ethoxylate units (NPE9.5; 0, 0.01, 0.1, 1.0 mg/L) on the reproduction of the snail Biomphalaria tenagophila. Adult snails (F0 generation) were exposed to NPE for 8 weeks. The F1 generation continued to be exposed from embryo to reproductive maturity while their descendants (F2) were exposed until day 10 after spawning. We determined the effects of NPE9.5 on the fecundity (8-week production of eggs and egg masses) of mature F0 and F1 snails. Developmental toxicity was investigated in F1 and F2 embryos. The two highest concentrations of NPE9.5 reduced the fecundity of F0. In the F1 generation, the lowest concentration enhanced the number of eggs laid per snail while the intermediate concentration had no effect and the highest one decreased the fecundity thereby suggesting a biphasic effect of NPE9.5. Study-derived NOECs (no-observed-effect-concentrations) for NPE were: fecundity, F0=10 microg/L, F1<10 microg/L; developmental toxicity, F1=100 microg/L, F2<10 microg/L. Results, therefore, indicated that B. tenagophila is highly vulnerable to NPE and that trans-generation exposure to NPE9.5 aggravates its reproductive toxicity.

Effects of copper on the egg development and hatching of a freshwater pulmonate snail Lymnaea luteola L.

“…Physa fontinalis [48] Trybutylin (TBT) 125 ng l −1 Egg production and cellular structure L. stagnalis [4] Nonylphenol ethoxylate 0.1-1 .mg l −1 Reduced fecundity, reduction in the Number of egg produced per snail, Egg masses, decreased, incidence of malformed snail eggs and hatching delay B. tenagophila [61] The average concentrations of copper in river sediment of the Gomati River (Lucknow, India) a tributary of the Ganges could reach up to 37 g l −1 [25] and at such high ambient Cu concentrations many gastropods including L. luteola and their developing stages would be expected suffer adversely. The endpoints suggested in the study can be used to establish biomarkers that are specific and sensitive indicators for the presence of Cu and possibly of other environmental pollutants in the aquatic environment.…”

Susceptibility of non-target invertebrates to Brazilian microbial pest control agents

“…Estimated concentrations were obtained after count the number of spores in a gram of lyophilized material and then diluted in respective dilutions. (Oliveira-Filho and Paumgartten 2000;OliveiraFilho et al 2004;Oliveira-Filho et al 2005;Oliveira-Filho et al 2009a;Oliveira-Filho et al 2009b). Assays were conducted in 3,000 ml beakers containing 2,000 ml of synthetic soft water (pH 7.4 ± 0.1, water hardness 44 mg/l as CaCO 3 ) at 25 ± 2°C.…”

Implications of water hardness in ecotoxicological assessments for water quality regulatory purposes: a case study with the aquatic snail Biomphalaria glabrata (Say, 1818)

“…These organisms were maintained for 5 weeks in waters with different hardness and because they are a hermaphrodites the evaluation of reproduction at the individual level was chosen as endpoint. To recover egg masses laid by snails, beakers were internally covered with cellophane sheets as suggested by Olivier and Haskins (1960) and adapted by Oliveira-Filho et al (2009a, b, 2010. To determine the number of eggs and egg-masses counts were performed twice a week.…”

“…Regarding laboratory observation of chronic effects on aquatic species, although the seven-day Ceriodaphnia dubia survival and reproduction test is one of the most adopted (Oliveira-Filho et al, 2008), alternative and often more sensitive tests have been evaluated (Oliveira-Filho et al, 2009a, b, 2010, with wide application potential, including tests with environmental samples.…”