9.3 Pesticides
The pesticide group contributes to the major percentage of chiral pollutants in the
environment. According to Ulrich et al. (2001, 2012, 2018), about 28% among 1693
pesticides exhibit a chiral character. In total, about 475 pesticides are released into
the environment as chiral compounds.
The most relevant sources of chiral contaminants are industrial wastewater,
domestic sewage, agricultural runoff and forestry activities that, in particular, during
the rainy season and irrigation processes contaminate the surface and ground water.
Pesticides are also used in household activities, thus also contributing to the contamination of our environment (Ali and Aboul-Enein 2004). The waste waters from
communities pollute rivers, oceans, ground water, sediments and soil. In addition,
pesticides are sprayed into the atmosphere, thus forming air-borne contaminants.
Many pesticides are persistent pollutants in the environment. These pesticides
often evaporate into the atmosphere, thus resulting in atmospheric pollution (Shen
et al. 2005; Wang et al. 2005, 2016; Bidleman et al. 2006; Daly et al. 2007; Ding
et al. 2007; Shen et al. 2009; Genualdi et al. 2011; Zhang et al. 2012). The
volatilisation of chlordane, heptachlor and heptachlor exo-epoxide pesticides has
been reported by several research groups. Bidleman and co-workers (Falconer et al.
1995; Jantunen and Bidleman 1998; Bidleman and Falconer 1999; Bidleman et al.
2002)
conducted
widespread
studies
of
air/water
exchange
of
α-hexachlorocyclohexane (α-HCH) in Resolute Bay and Arctic Ocean water. The
authors describe that air pollution is caused owing to the volatilisation of α-HCH
from lake water. Jantunen and Bidleman (1996) describe α-HCH concentrations in
water and air by the fugacity ratio. Harner et al. (1999) attribute the eastern Arctic
Ocean to be a contamination source of α- and γ-hexachlorocyclohexane using the
enantiomeric ratio of α-hexachlorocyclohexane. Many working groups used the
ratios of p,p
0 -DDT/p,p
0 -DDE (DDT, dichlorodiphenyltrichloroethane; DDE,
dichlorodiphenyldichloroethylene) and o,p
0 -DDT/p,p
0 -DDT to identify the pollution
sources of DDTs (Kurt-Karakus et al. 2005; Olafsdottir et al. 2005; Kim et al. 2008;
Liu et al. 2009; Zhang et al. 2010; Venier and Hites 2014; Devi et al. 2015; Yadav
et al. 2016). A small value of the p,p
0 -DDT/p,p
0 -DDE ratio is suggestive of aged
DDTs and a value higher than 1.0 shows recent application or production because of
degradation of DDTs to DDEs in the environment. The ratio of o,p
0 -DDT/p,p
0 -DDT
is also suggestive of the source type. Some important case studies, having in mind
this background, are discussed in the following paragraphs.
Yeo et al. (2004) reported that chlordane and DDTs had been banned in Korea
since the 1970s but that these pesticides are still present in the atmosphere. The
authors attributed this phenomenon to sources of volatilisation from soil and sediments. Park et al. (2011) carried out a (Park et al. 2011) monitoring program in 2008
to monitor persistent organic pollutants (POPs) in Korea. The authors determined
pollution sources dependent on the geographical location, thus inferring long-range
transport to the atmosphere.
9.3 Pesticides
257
The pesticide group contributes to the major percentage of chiral pollutants in the
environment. According to Ulrich et al. (2001, 2012, 2018), about 28% among 1693
pesticides exhibit a chiral character. In total, about 475 pesticides are released into
the environment as chiral compounds.
The most relevant sources of chiral contaminants are industrial wastewater,
domestic sewage, agricultural runoff and forestry activities that, in particular, during
the rainy season and irrigation processes contaminate the surface and ground water.
Pesticides are also used in household activities, thus also contributing to the contamination of our environment (Ali and Aboul-Enein 2004). The waste waters from
communities pollute rivers, oceans, ground water, sediments and soil. In addition,
pesticides are sprayed into the atmosphere, thus forming air-borne contaminants.
Many pesticides are persistent pollutants in the environment. These pesticides
often evaporate into the atmosphere, thus resulting in atmospheric pollution (Shen
et al. 2005; Wang et al. 2005, 2016; Bidleman et al. 2006; Daly et al. 2007; Ding
et al. 2007; Shen et al. 2009; Genualdi et al. 2011; Zhang et al. 2012). The
volatilisation of chlordane, heptachlor and heptachlor exo-epoxide pesticides has
been reported by several research groups. Bidleman and co-workers (Falconer et al.
1995; Jantunen and Bidleman 1998; Bidleman and Falconer 1999; Bidleman et al.
2002)
conducted
widespread
studies
of
air/water
exchange
of
α-hexachlorocyclohexane (α-HCH) in Resolute Bay and Arctic Ocean water. The
authors describe that air pollution is caused owing to the volatilisation of α-HCH
from lake water. Jantunen and Bidleman (1996) describe α-HCH concentrations in
water and air by the fugacity ratio. Harner et al. (1999) attribute the eastern Arctic
Ocean to be a contamination source of α- and γ-hexachlorocyclohexane using the
enantiomeric ratio of α-hexachlorocyclohexane. Many working groups used the
ratios of p,p
0 -DDT/p,p
0 -DDE (DDT, dichlorodiphenyltrichloroethane; DDE,
dichlorodiphenyldichloroethylene) and o,p
0 -DDT/p,p
0 -DDT to identify the pollution
sources of DDTs (Kurt-Karakus et al. 2005; Olafsdottir et al. 2005; Kim et al. 2008;
Liu et al. 2009; Zhang et al. 2010; Venier and Hites 2014; Devi et al. 2015; Yadav
et al. 2016). A small value of the p,p
0 -DDT/p,p
0 -DDE ratio is suggestive of aged
DDTs and a value higher than 1.0 shows recent application or production because of
degradation of DDTs to DDEs in the environment. The ratio of o,p
0 -DDT/p,p
0 -DDT
is also suggestive of the source type. Some important case studies, having in mind
this background, are discussed in the following paragraphs.
Yeo et al. (2004) reported that chlordane and DDTs had been banned in Korea
since the 1970s but that these pesticides are still present in the atmosphere. The
authors attributed this phenomenon to sources of volatilisation from soil and sediments. Park et al. (2011) carried out a (Park et al. 2011) monitoring program in 2008
to monitor persistent organic pollutants (POPs) in Korea. The authors determined
pollution sources dependent on the geographical location, thus inferring long-range
transport to the atmosphere.
9.3 Pesticides
257