Influence of novel lignocellulosic residues in a biobed biopurification system on the degradation of pesticides applied in repeatedly high doses

Background: The biobed is a simple biopurification system used to prevent the point-source pesticide contamination that occurs at farm level. The typical composition of the biomixture used in this system is soil, peat and straw in volumetric proportions of 1:1:2. The principal component is straw due to its positive effects on biological activity and thus pesticide degradation. However, access to straw can be limited in some regions, so it must be replaced by other more readily available lignocellulosic residues. Results: Therefore, two alternate lignocellulosic materials (barley husks and pine sawdust) were evaluated as partial substitutes for straw. The degradation of a repeatedly applied mixture of six pesticides by these alternates was assessed. The microbial respiration and fluorescein diacetate (FDA) hydrolysis activity were also assessed. The results showed that the highest degradation efficiency was found in mixtures containing straw and barley husks. Each biomixtures tested achieved a high degradation (50 to 90%) of all the pesticides used except iprodione. Repeated applications of pesticides resulted in a slowing of the degradation rate of all pesticide types in all biomixtures. FDA activity and microbial respiration were higher in the biomixtures containing barley husks and straw compared to the mixture with pine sawdust, a result consistent with the pesticide degradations observed. Conclusions: This paper demonstrates that the straw in the traditional biomixture can be partially replaced by other lignocellulosic materials to efficiently degrade a mixture of pesticides, even when the pesticides are added in successive applications and high concentrations.

Effect of malathion on reproductive system of male rats.

The pesticides are one of the most potentially harmful chemicals liberated in the environment in an unplanned manner Malathion is widely used as a potent pesticide in many countries and has been shown to produce some adverse health effects. A study was conducted to asses the effects of malathion on the male reproductive system of wistar rats. The pesticide was administered to rats orally at dose levels of 50, 150 and 250 mg/kg/body wt/day for 60 days. In comparison to the control rats, there was a significant reduction in the weight of testes, epididymis, seminal vesicle and ventral prostate. Testicular and epididymal sperm density were decreased in the animals treated with malathion. Pre and post fertility test showed 80% negative results after treatment Biochemical profile of the testis revealed a significant decline in the contents of sialic acid and glycogen. Whereas a significant increase in the protein content of testis and testicular cholesterol was observed. The activity of testicular enzyme acid phosphatase increased significantly while decreased alkaline phosphatase activity was found. Malathion also suppressed the level of testosterone significantly Results of the present study clearly suggest that malathion induce toxic effects on the male reproductive system of rats.

Fat and oil inhibit phosphine release from aluminium phosphide--its clinical implication.

Poisoning by suicidal or accidental ingestion of aluminium phosphide (AlP) is a frequent medical emergency seen all over the world. AlP, a grain fumigant and rodenticide, on exposure to moisture, liberates highly toxic gas, phosphine. The rapidly inhibits mitochondrial respiration and has cytotoxic action. No specific antidote is known against it till date and prognosis depends much on dose and time lag between AlP ingestion and the stomach wash in the hospital (critical period). Physicochemical properties of AlP and nonmiscibility of fat and water promoted us to study the effect of different fats and oils as possible antidotes to inhibit phosphine liberation. In vitro experiments revealed that vegetable oils and liquid paraffin were much more effective than butter and ghee in inhibiting release of phosphine from AlP. These findings may have significant clinical implication.

Manual de diagnóstico y tratamiento de intoxicaciones agudas causadas por plaguicidas

Presenta los aspectos generales de los plaguicidas, la clasificación, tipo de organofosforados y carbamatos, asi como sus propiedades físico-quimicas de los organofosforados; toxicocinetica y toxicodinamica de los plaguicidas organofosforados y carbamatos; vias de absorción proceso de biotransformación y de eliminación; mecanismo de acción sobre el organismo; diagnostico de la intoxicación aguda; historia clínica; pruebas de laboratorio; tratamiento; tratamiento médico