Microbe-assisted degradation of aldrin and dieldrin

Aldrin and dieldrin are extensively used as synthetic pesticides in the agricultural industry, which classified as persistent organic pollutants (POPs). Although these compounds have been prohibited over the past decades in most countries, they are still found in the environment. Many studies have shown the microbial transformation of aldrin to dieldrin as main metabolic product, which has higher toxicity and persistence. However, some microorganisms had ability to convert dieldrin to some metabolic compounds. Furthermore, some studies have also revealed that dieldrin could be mineralized to CO₂. In general, degradation of aldrin and dieldrin by fungi is faster than that of bacteria of which degradation pathway is clearly described. The efficiency of degrading microorganisms, introduced into contaminated sites, depends on many factors such as, pH, carbon and nitrogen sources, enzymes, hormones, and light. Some enzymes had been found to be involved in aldrin and dieldrin degradation.