DDT in the Biosphere: Where Does It Go?

Abstract

The worldwide pattern of movement of DDT residues appears to be from the land through the atmosphere into the oceans and into the oceanic abyss. Calculations based on the fragmentary data available on. rates of movement and sizes of various pools of DDT residues lead to the conclusion that concentrations in the atmosphere and in the mixed layer of the oceans lag by only a few years behind the amounts of DDT used annually throughout the world. A model suggests that maximum concentrations of DDT residues occurred in air in 1966 and will occur in the mixed layer of the oceans in 1971. The biota probably contains in total less than 1/30 of 1 year's production of DDT during the mid-1960's, a very small amount in proportion to the total potentially available. The reason for the biota's failure to absorb larger quantities and to be affected much more severely is unclear. The analysis suggests that mere good fortune has protected man and the rest of the biota from much higher concentrations, thus emphasizing the need to determine the details of the movement of DDT residues and other toxins through the biosphere and to move swiftly to bring world use of such toxins under rational control based on firm knowledge of local and worldwide cycles and hazards.

Occurrence and distribution of organochlorine pesticides (HCH and DDT) in sediments collected from East China Sea

“…Organochlorine pesticides (OCPs), including typical representatives of this group of chemicals such as technical hexachlorocyclohexane (HCH) and 1,1,1-trichloro-2,2-bis(4-chlorophenyl)ethane (DDT), have been extensively studied in the last 30 years, due to their large production and usage, their impact on non-target organisms, bioaccumulation, and persistence in the environment (Woodwell et al, 1971;Tanabe et al, 1982;Iwata et al, 1994;Lee et al, 2001). In aquatic environment, these compounds can enter marine and freshwater ecosystems through effluents release, atmospheric deposition, runoff, and other means (Zhou et al, 2001).…”

Rates and Routes of Transport of PCBs in the Environment

“…Possible routes into the environment include: (1) leaks from sealed transformers and heat exchangers; (2) leaks of PCB-containing fluids from hydraulic systems which are only partially sealed; (3) spills and losses in the manufacturing either of PCBs or PCB-containing fluids; (4) vaporization or leaching from PCB-containing formulations; (5) disposal of waste PCBs or PCB-containing fluids.…”

Global gridded emission inventories of α‐hexachlorocyclohexane

“…Although only the ¾-HCH exhibits any significant insecticidal activity, all isomers are acutely and chronically toxic [Metcalf, 1955 The use of technical HCH and other organochlorine insecticides contributes to increased agricultural yield, protection of livestock, and the reduction of vector-transmitted disease. On the other hand, the global contamination caused by usage of technical HCH and other pesticides over the past 5 decades has been identified in virtually every environmental compartment and every geographic region [Woodwell et al, 1971;Waid, 1986; Tanabe, tive understanding of those links between use and contamination has been gained by analyzing and interpreting concentrations in samples and the usage of pesticides, some efforts at quantitatively describing the overall picture of the global fate of HCH have also been undertaken by modelers [Pudykiewicz and McMitlan, 1992;Pudykiewicz, 1998;Strand and Hov, 1996;Wania and Mackay, 1996;Wania et aL, 1999]. Recently, by using a zonally averaged global multimedia distribution model, Wania et at.…”