Nonylphenol (NP) and octylphenol (OP), both of which are biodegradation products of alkylphenols, are widely used in industrial applications and in some domestic products. These chemicals are found widely in surface water and aquatic sediments. We have carried out a comparative embryotoxicity analysis of the effects of increasing concentrations of NP (seven concentrations ranging from 0.937 to 18.74 microg/l) and OP (six concentrations ranging from 5 to 160 microg/l) on embryos of the sea urchin Arbacia lixula. The indicators evaluated were larval malformations, developmental arrest and embryonic/larval mortality. The results revealed that low concentrations of these chemicals (NP, OP) generally caused malformations in the skeletal system. High concentrations (18.74 microg NP/l, 160 microg OP/l) were found to inhibit the growth of embryos in the early life stages by preventing mitosis. We conclude that NP and OP present a major risk to the normal development of A. lixula at the low concentrations that have been recorded in the environment. These chemicals are therefore most likely to represent an ecological hazard at the population level given the cumulative effects of other environmental pollutants.

No abstract

Micronuclei tests is a system of mutagenicity testing used for determining the pollution and chemicals causing changes in DNA fragments such as micronuclei in the cytoplasm of interphase cells. Damage caused on the DNA by genotoxic pollutants is the first consequence occurring in the aquatic organisms. Thus, it was attempted to determine whether pollution affected the erythrocytes and gills of fish Gobius niger and haemolymph and gills of mussels Mytilus galloprovincialis living in Izmir Bay at the level of DNA by the means of micronuclei (MN) test. Organisms used in the MN test were collected from seven locations (Alsancak, Alaybey Shipyard, Karsiyaka, Bostanli, Göztepe, Konak and Pasaport) which are known as the most polluted part of inner Bay of Izmir (Western Coast of Turkey). According to the results of the present study, frequency of MN was found at high level in Alaybey Shipyard and Pasaport where wastes from existing dockyard contributed to high level of pollution. In conclusion, this study indicates that the micronuclei test gives sensitive results in monitoring the pollution, especially the pollution of harbor, and thus it might be used as standard method in regular monitoring of pollution of coastal ecosystem.

No abstract

In this study, embryotoxic and genotoxic effects of nonylphenol (NP) and octylphenol (OP), which are the derivates of alkylphenol (APs), were evaluated using the gametes and embryos of the sea urchin Paracentrotus lividus. The sperm and eggs of sea urchins were exposed to increasing concentrations of NP (0.937-18.74 microg/L) and OP (5-160 microg/L) under static conditions. The endpoints were sperm fertilization success, quantitative and morphologic changes in mitotic activity, larval malformations, developmental arrest, and embryonic/larval mortality. A dose-response-related reduction (approximately 20%) was observed in fertilization success and significant increases in the number of larvae with skeleton malformations at the pluteus stage of the contaminated sperms. The spermiotoxic and embryotoxic concentrations were determined as 0.937 microg/L for NP and 4.685 microg/L for OP for this species. The embryotoxicity of NP and OP is concentration dependent, and significant growth reduction at the early life stages and an increase in larval malformations as skeleton deformities at the pluteus stage were observed. Cytogenetic analysis of embryos showed a decreasing curve in mitotic indexes (number of mitosis per embryo) with increasing concentrations of NP and OP. It can be concluded that NP and OP adversely affect the reproduction and embryonic developmental stages of the P. lividus and this is of great ecological importance because of the hazard at the population level.