Environmental Engineering Reference
In-Depth Information
TABLE 7.3 (Continued)
Selected Pesticide and Degradation Product Concentrations in Rainwater
Pesticide in Rainwater
Range (mg/L)
Site
References
Phosalone
<LD-0.010
Rural
Aulagnier et al. (2008)
Phosmet
0-0.047
Rural
Vogel et al. (2008)
Phosmet
<LD-0.062
Rural
Aulagnier et al. (2008)
Prometon
0-0.0122
Rural
Vogel et al. (2008)
Prometryn
0-0.031
Rural
Vogel et al. (2008)
Pronamide
0-0.017
Rural
Vogel et al. (2008)
Propachlor
0-0.163
Rural
Vogel et al. (2008)
Simazine
0-15.6
Rural
Vogel et al. (2008)
Terbuthylazine
0-0.014
Rural
Vogel et al. (2008)
Terbuthylazine
<LQ-1.06
Urban (near crops)
Sauret-Szczepanski et al. (2006)
Terbuthylazine
0.005-0.025
Rural
Bossil et al. (2002)
Trifluralin
0-0.148
Rural
Vogel et al. (2008)
Trifluralin
0.05-3.44
Rural
Trevisan et al. (1993)
Trifluralin
<0.002-0.01
Rural
Coupe et al. (2000)
Range covers minimum to maximum concentration detected.
LD, limit of detection (for more details, see references); LQ, limit of quantification (for more details, see
references).
The question of whether some kinds of soils are significant long-term sources of persistent
pesticides to the atmosphere lacks a consensus answer. Shunthirasingham et al. (2010) con-
cluded that the arid soils of the subtropical regions cannot be considered either major reservoirs
of pesticides or important long-term sources of pesticides. They investigated the concentration
levels, spatial trends, and seasonal variability of pesticides in air and soil in Botswana. Even
in areas that had been sprayed with DDT and endosulfan repeatedly in the past, these authors
found low levels of pesticides in the gas phase, with α-endosulfan and lindane being the most
abundant. In fact, they concluded that the spatial and seasonal patterns observed were more
likely related to pesticide usage than to environmental factors or historical use.
In India, between December 2006 and March 2007, some authors (Chakraborty et al.
2010) studied samples from seven different cities and found the following mean concen-
tration levels of organochlorine pesticides: 5400 pg/m 3 of Hexachlorocyclohexane (HCHs),
1470 pg/m 3 of DDTs, 1530 pg/m 3 of chlordanes, 1040 pg/m 3 of endosulfans, and 790 pg/m3
of hexachlorobenzene. These authors concluded that the data showed a decrease in the
concentrations of HCHs and DDTs for most regions. Lindane dominated the HCHs due
to its widespread use in India. In fact, lindane is one of the most studied and measured
persistent compounds.
7.5 Fate in the Atmosphere
Pesticides behave in the atmosphere in the same way as other volatile and semivolatile
organic compounds. As explained in the previous sections, pesticides can be distributed
between the gas, particle, and aqueous phases, and this partitioning depends on both
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