The pharmaceutical use of permethrin: sources and behavior during municipal sewage treatment

Abstract

Permethrin entered use in the 1970s as an insecticide in a wide range of applications, including agriculture, horticultural, and forestry, and has since been restricted. In the 21st century, the presence of permethrin in the aquatic environment has been attributed to its use as a human and veterinary pharmaceutical, in particular as a pedeculicide, in addition to other uses, such as a moth-proofing agent. However, as a consequence of its toxicity to fish, sources of permethrin and its fate and behavior during wastewater treatment are topics of concern. This study has established that high overall removal of permethrin (approximately 90%) was achieved during wastewater treatment and that this was strongly dependent on the extent of biological degradation in secondary treatment, with more limited subsequent removal in tertiary treatment processes. Sources of permethrin in the catchment matched well with measured values in crude sewage and indicated that domestic use accounted for more than half of the load to the treatment works. However, removal may not be consistent enough to achieve the environmental quality standards now being derived in many countries even where tertiary treatment processes are applied.

Spermiotoxicity and embryotoxicity of permethrin in the sea urchin Paracentrotus lividus

Abstract

The toxicity of permethrin on the fertilization and early development of sea urchin Paracentrotus lividus embryos were studied. Spermiotoxicity was evaluated on the basis of fertilization rate. Embryotoxicity was determined by comparing the frequency of normal development and malformations in embryos exposed to permethrin throughout their development. Permethrin inhibited fertilization success, and yielded IC25 and IC50 values of 0.58 (CL = 0.44-0.77) and 0.94 (CL = 0.92-0.95) µg/L, respectively. The embryotoxicity of permethrin was concentration dependent indicating a decreased percentage of normally developed plutei with increasing permethrin concentrations: IC25 = 0.195 µg/L (CL = 0.15-0.26) and IC50 = 0.346 µg/L (CF = 0.29-0.41). Associated with the decrease in normal pluteus frequency was an increase in larval malformations as skeleton deformities. The results suggest that permethrin is more highly toxic to embryos than to sperm, and that this insecticide may present a potential risk for the sea urchin in contaminated marine environments.