Mutagenic and carcinogenic effects of pesticides

Magnetic solid-phase extraction based on modified ferum oxides for enrichment, preconcentration, and isolation of pesticides and selected pollutants

Recently, a simple, rapid, high-efficiency, selective, and sensitive method for isolation, preconcentration, and enrichment of analytes has been developed. This new method of sample handling is based on ferum oxides as magnetic nanoparticles (MNPs) and has been used for magnetic solid-phase extraction (MSPE) of various analytes from various matrices. This review focuses on the applications of modified ferum oxides, especially modified Fe3O4 MNPs, as MSPE adsorbent for pesticide isolation from various matrices. Further perspectives on MSPE based on modified Fe3O4 for inorganic metal ions, organic compounds, and biological species from water samples are also presented. Ferum(III) oxide MNPs (Fe2O3) are also highlighted.

Synthesis and Herbicidal Activity of New Hydrazide and Hydrazonoyl Derivatives

Three new hydrazide and five new hydrazonoyl derivatives were synthesized. The chemical structures of these compounds were confirmed by ¹H-NMR, IR spectroscopy and elemental analysis. The prepared compounds were tested for their activity to inhibit photosynthetic electron transport in spinach chloroplasts and growth of the green algae Chlorella vulgaris. IC₅₀ values of these compounds varied in wide range, from a strong to no inhibitory effect. EPR spectroscopy showed that the active compounds interfered with intermediates Z^•/D^•, which are localized on the donor side of photosystem II. Fluorescence spectroscopy suggested that the mechanism of inhibitory action of the prepared compounds possibly involves interactions with aromatic amino acids present in photosynthetic proteins.

Allium cepa chromosome aberration and micronucleus tests applied to study genotoxicity of extracts from pesticide-treated vegetables and grapes

The Allium cepa assay is an efficient test for chemical screening and in situ monitoring for genotoxicity of environmental contaminants. The test has been used widely to study genotoxicity of many pesticides revealing that these compounds can induce chromosomal aberrations in root meristems of A. cepa. Pesticide residues can be present in fruit and vegetables and represent a risk for human health. The mutagenic and carcinogenic action of herbicides, insecticides and fungicides on experimental animals is well known. Several studies have shown that chronic exposure to low levels of pesticides can cause birth defects and that prenatal exposure is associated with carcinogenicity. This study evaluated the potential application of plant genotoxicity tests for monitoring mutagens in edible vegetables. The presence of pesticides and genotoxic compounds extracted from 21 treated vegetables and eight types of grapes sampled from several markets in Campania, a region in Southern Italy, was monitored concurrently. The extracts were analysed for pesticides by gas chromatography and high-performance liquid chromatography, and for genotoxicity using two plant tests: the micronucleus test and the chromosomal aberration test in A. cepa roots. Thirty-three pesticides were detected, some of which are not approved. Genotoxicity was found in some of the vegetables and grapes tested. Allium cepa tests proved to be sensitive in monitoring genotoxicity in food extracts. The micronucleus test in interphase cells gave a much higher mutagenicity than the chromosomal aberration test in anaphase-telophase cells.

Butachlor, a suspected carcinogen, alters growth and transformation characteristics of mouse liver cells

Butachlor is a widely used herbicide in Asia and South America. Previous investigations have indicated that it is a suspected carcinogen. To understand more about the biological effects of butachlor on cultured cells and the mechanism(s) of its carcinogenicity, we studied the alteration of the growth characteristics that was induced by butachlor in normal mouse liver cells (BNL CL2). This study demonstrates that butachlor decreases the population-doubling time of BNL CL2 cells, suggesting that it stimulates cell proliferation. To support this finding, a thymidine incorporation assay was conducted and a similar result that butachlor stimulates cell proliferation was elucidated. In addition, we show that butachlor increases the saturation density of the BNL CL2 cells. When combined with the tumor initiator N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), butachlor transforms cells efficiently, as demonstrated by loss of contact inhibition. These findings indicate that butachlor alters the growth characteristics of BNL CL2 cells and suggest that butachlor may induce malignant transformation through stimulation of cell proliferation, alteration of cell cycle regulation, and suppression of cell density-dependent inhibition of proliferation.

ATSDR evaluation of health effects of chemicals. II. Mirex and chlordecone: health effects, toxicokinetics, human exposure, and environmental fate

This document provides public health officials, physicians, toxicologists, and other interested individuals and groups with an overall perspective of the toxicology of mirex and chlordecone. It contains descriptions and evaluations of toxicological studies and epidemiological investigations and provides conclusions, where possible, on the relevance of toxicity and toxicokinetic data to public health. Additional substances will be profiled in a series of manuscripts to follow.

Mutagenic and carcinogenic pesticides used in the agricultural environment of Gaza Strip

More than 100 metric tons of formulated pesticides (about 75 pesticides) are used annually in Gaza Strip. It was found that 19 of these pesticides, that have been used, are internationally suspended, cancelled and banned pesticides. About 1100 cases of cancer have been registered in Gaza Strip (1979-1983). The distribution of cancer types among those patients are lymphoma and hematological malignancy, breast, head and neck, gastrointestinal malignancy, reproductive system, urinary system, soft tissue tumors, brain tumors and others. Consequently, the introduction and heavy use of pesticides and other toxic substances in the Gaza Strip environment is suspected to correlate with the growing incidence of cancer and other abnormalities in the nation. Precise determination of the effects of chronic exposure is, therefore, urgently needed.

Hepatic microsomal enzymes in S. mansoni infected mice: II. Effect of duration of infection and lindane administration on aminopyrine demethylase and aniline hydroxylase

The time course of effects of S. mansoni infection on hepatic microsomal drug metabolizing enzymes was studied in swiss albino mice. Aminopyrine demethylase and aniline hydroxylase showed increases in activity, reaching a peak 30 days post infection. Both enzymes demonstrated a steady decline thereafter. On day 60, the level of aminopyrine demethylase was comparable to that of uninfected mice. On the other hand, the activity of aniline hydroxylase was lower than the control values. Treatment with lindane (40 mg/Kg/day X 3) increased the activity of both enzymes after different durations of disease induction. Changes in hepatic microsomal enzymes in S. mansoni infection may alter the intensity and duration of pharmacologic or toxic effects of drugs eliminated from the body through metabolic transformation.