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Solid phase anaerobic bioremediation of soil from the "tomb" area contaminated with chlorinated pesticides

Baczyński T.

Archives of Environmental Protection

2009

Vol. 35, no. 3

123-133

The paper presents results of laboratory tests of solid-phase anaerobic biorcmediation of soil contaminated with chlorinated pesticides. It was shown that using methanogenic granular sludge as inoculum and lactate as electron donor, it is possible to remove 80% of y-HCH, 94% of methoxyehior and 93% of DDT against control sample, with DDD accumulation much less than stoichiometric. Pesticides removal was practically completed alter 4-6 weeks of incubation at 22°C. Additional application of nonionic surfactant Tween 80 resulted in about one and a half-fold decrease of residual concentrations of some compounds. It also enhanced DDT conversion to some extent, decreasing DDD accumulation and intensifying production of DBP, the terminal metabolite of DDT anaerobic degradation pathway. Use of methanol as electron donor produced effects quite similar to these obtained with lactate, however with reduced results scatter.

Artykuł przedstawia wyniki badań laboratoryjnych nad beztlenową bioremediacją gruntu zanieczyszczonego pestycydami chlorowanymi, prowadzoną w fazie stałej. Stwierdzono, że przy zaszczepieniu metanogennym osadem granulowanym oraz użyciu mleczanów jako donora elektronów możliwe jest usunięcie 80% y-HCH, 94% mctoksychloru i 93% DDT w odniesieniu do próby kontrolnej, przy akumulacji DDD znacząco mniejszej od stechiometrycznej. Usuwanie pestycydów było praktycznie zakończone po 4-6 tygodniach inkubacji w temperaturze 22°C. Zastosowanie dodatku niejonowego środka powierzchniowo czynnego Tween 80 skutkowało około półtorakrotnym obniżeniem stężeń resztkowych niektórych związków. Spowodowało ono także pewną intensyfikację przemian DDT, przejawiającą się obniżeniem akumulacji DDD oraz zwiększeniem produkcji DBP, będącego ostatecznym produktem beztlenowej degradacji DDT. Wykorzystanie metanolu w roli donora elektronów przyniosło rezultaty zasadniczo podobne jak w przypadku mleczanu, jednakże przy zmniejszonym rozrzucie wyników.

Krótki kurs historii POP. Część pierwsza : DDT

Mastalerz P.

Wiadomości Chemiczne

2003

[Z] 57, 7-8

671--775

Since the discovery of its marvellous insecticidal properties by Paul Mueller in 1939, DDT continues to stir human minds and to inspire countless scientists to study DDT effects on living creatures, from bacteria and insects to humans. There is probably no other chemical compounds which was studied as extensively and thoroughly as DDT and which provoked so many discussions and contradictory opinions. DDT was prized as the most useful compound which saved millions from unnecessary death due to malaria but was also condemned as a deadly poison threatening the life on Earth. It is important to know where is the truth. This article was inspired by the fact that the voices of condemnation prevail in popular and scientific literature and, in the consequence, most people believe that DDT is harmful and its banning was prudent. However, the truth is quite different but it is deeply buried and difficult to find in the multitude of publications dealing with the biological properties of DDT. The problem is more difficult because of the fact that the oldest and most fundamental papers on biological activity of DDT are now forgotten and are never quoted in recent literature. My purpose is to remedy that situation by giving an unbiased picture of the good and bad sides of DDT such as emerges from a thorough search of the literature. In this article I provide evidence that the ban of DDT was a very serious mistake and that DDT continues to serve the mankind in its fight against malaria, in disregard of all bans and condemnations. Nobody seems to remember now that after the ban in 1970s the temporary retreat from using DDT against mosquitoes killed several hundred million people which unnecessarily died of malaria. It appears that DDT ban stands out as the biggest homicidal act in all history of mankind. Responsibility is of course with politicians who voted for the ban and the scientists who advised them to do so. There are still other reasons why it was necessary to write this article. My purpose is not to vindicate DDT but to expose the multitude of false opinions about that insecticide. Thus, it is not true that DDT is cancerogenic in humans or that its hormonal properties threaten our survival, as prophesized by authors of some recent books. It is also not true that DDT was ever a serious hazard for fish and wildlife. DDT never threatened hawks and eagles or pelicans and the countless papers which say otherwise are simply wrong. I provide plenty of published evidence in support of my efforts to rectify mistakes and deliberate lies which are so common in the literature on biological efffects of DDT. Unfortunately my litereature search revealed that in several cases the public was deliberately misled by scientists, who helped with their publications to spread false opinions about DDT. This provokes severe doubts concerning the integrity of ecologically minded scientists.