Acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and carboxylesterase (CbE) activities have been measured in gills and digestive gland of the mussel Mytilus galloprovincialis. AChE activity was predominantly localized in gills, whereas the highest BChE and CbE specific activities were detected in digestive glands. Commonly used pesticides were examined in vitro for their ability to inhibit mussel esterases; the results obtained pointed out the highest sensitivity of mussel CbE to low concentrations of pesticides, but also the higher sensitivity of gill cholinesterases over digestive gland forms. Seasonal variation in the activity of gill esterases was determined monthly in mussels collected from the Ebro Delta, an area where pesticides and biocides are frequently used. As a general trend, elevated cholinesterase activities were detected in winter, possibly indicating little or no exposure to organophosphorous compounds, whereas the lowest cholinesterase activities were reported over the summer period. These changes were related to agricultural activities in the area and are supported by the detection of organophosphorous pesticides in the tissue of M. galloprovincialis.

The use of cholinesterase and carboxylesterase activities from Mytilus galloprovincialis in pollution monitoring

Effects of Bisphenol A on the microalga Chlamydomonas reinhardtii and the clam Corbicula fluminea.

Among UV-filters, benzophenones are one of the most abundantly used and detected groups in the environment. Bisphenols are also one of the most widely used chemicals in plastics, but their demonstrated deleterious effects on several organisms and humans have led to the production of alternative analogues. However, few comparative studies on the ecotoxicological effects of these derivatives or analogues have been carried out. The present study aimed to investigate the effects of two benzophenones (BP-3 and BP-4) and two bisphenols (BPA and BPS) in a short-term exposure of the freshwater endobenthic bivalve Corbicula fluminea. Clams were exposed for 96 h to several concentrations of the four pollutants: BP-3 (0.63; 1.25; 2.5; 5 mg l−1), BP-4 (4.75; 9.5; 19; 38 mg l−1), BPA (3.75; 7.5; 15; 30 mg l−1), and BPS (2.5; 5; 10; 20 mg l−1). The comparative acute toxicity of these pollutants was evaluated by the analysis of the post-exposure filtering capacity of clams, lipid peroxidation (LP) levels and the activity of the antioxidant enzymes catalase (CAT) and glutathione reductase (GR). After the exposure period, except for BP-4, the chemicals tested seemed to be detected by clams and provoked valve closure, decreasing filter-feeding in a concentration-dependent manner. Furthermore, C. fluminea exposed to the highest concentrations of BP-3, BP-4 and BPA showed a significant increase in LP, CAT and GR activities with respect to their controls. BP-3 and BPA were the most toxic compounds showing significant differences in all the parameters analysed at the highest concentrations assayed. However, clams exposed to BPS showed only significant alterations in filtration parameters and in GR activity, in the two highest concentrations tested, indicating that this compound was the least toxic to clams. Obtained results highlight the importance of investigating the effects that emerging pollutants have on aquatic organisms.

Comparative acute toxicity of benzophenone derivatives and bisphenol analogues in the Asian clam Corbicula fluminea

Apple snails are one of the most survived fresh water invasive species that causes massive economic loss to vegetations, especially to the rice fields. They survive against many environmental stressors and are considered as a major pest in water-lodged cultivated area due to their intrusiveness, adaptation mechanisms and survivability. Therefore, there is a need for strategies to control their population. Snails can also be used as pollution bioindicators. Here we review apple snails for their ecotoxic management without compromising environment and co-inhabitants, and their use as semi-sessile invasive ecotoxic marker species. Snails have been found to accumulate 0.19–0.21% biphenyl ethers, 1.65% copper sulphate with 26.7% morality, 1.53–29.7% ivermectin, 43% polybrominated biphenyl ethers, 59% triphenylphosphine oxide, 8–100% of various heavy metals and nanoparticles. Feed intake of apple snails can be enhanced up to 22% with copper supplements, while 17 and 100% mortality can be achieved with niclosamide monohydrate (0.13 mg/L) and tea seed derivatives (0.015 g/L) exposure, respectively. Snails respond to stress factors with up to 29.6% higher lipid peroxides and 1.06% protein carbonyls, along with up to 80, 240 and 127% higher activities of superoxide dismutase, catalase and glutathione peroxidase enzymes, respectively, after cypermethrin exposure. Oppositely, mercury (2–8 mg/L) and aldicarb can reduce their oxygen consumption and acetylcholinesterase activity of up to 88.1 and 96.08%, respectively.

M.L. Albá

Papers

A multilevel response approach reveals the Asian clam Corbicula largillierti as a mirror of aquatic pollution

What does the freshwater clam, Corbicula largillierti, have to tell us about chlorothalonil effects?