annual means for chlordane (Falconer et al. 1998; Ulrich and Hites 1998) at Sturgeon
Point on Lake Erie (0.034 ng/m
3 ). Ambient levels in two southern states were
somewhat higher at 0.109 ng/m
3 for rural Alabama and 0.295 ng/m
3 in the City of
Columbia, SC (Bidleman et al. 1998a, b, c, d). Average indoor air concentrations in
the Corn Belt states (16.7 ng/m
3 , n ¼ 20) were similar to average levels in homes in
Columbia (10.1 ng/m
3 , n ¼ 3) and rural Alabama (34.2 ng/m
3 , n ¼ 5).
Average enantiomeric ratios for trans- and cis-chlordane, heptachlor and heptachlor exoepoxide in air and soils from the Corn Belt region, South Carolina and
Alabama are summarised in Table 8.18.
Soils in the Corn Belt region show an enantiomeric difference for both trans- and
cis-chlordane: in the case of trans-chlordane, ER values less than 1.00 indicate the
preferential transformation of the (+)-enantiomer, while for cis-chlordane ER values
greater than 1.00 imply a preferential transformation of the (À)-enantiomer. A
comparison of enantiomeric ratios for Corn Belt soils and air-above soil samples
was carried out for six fields. The enantiomeric signatures of pesticides in the air
above the soil followed the same pattern as in the soil, both in direction of transformation and in relative magnitude. This preservation of ER profile on volatilisation is
in line with the results obtained for heptachlor, heptachlor exoepoxide and α-HCH
(Aigner et al. 1998; Bidleman et al. 1998a, b, c, d; Wiberg et al. 2001a, b). Chlordane
Table 8.18 Average enantiomeric ratios (ER ¼ (+)/(À)-enantiomer; Æ standard deviation) for
trans- and cis-chlordane, heptachlor and heptachlor exoepoxide in air and soil from the Corn Belt
region, South Carolina and Alabama (Aigner et al. 1998; Bidleman et al. 1998a, b, c, d)
Location
transChlordane
ER
cisChlordane
ER
Heptachlor
ER
Heptachlor exoepoxide Conc.
(pg/m
3
) ER
AIR
Above-soil, Cornbelt
(n ¼ 6)
0.74 (0.10)
1.11 (0.08)
Ambient, Cornbelt (n ¼ 3)
0.93 (0.03)
1.04 (0.04)
Indoor, Cornbelt (n ¼ 15)
0.99 (0.01)
0.98 (0.03)
Ambient, Alabama (n ¼ 20) 0.98 (0.03)
1.01 (0.04)
Ambient, SC (n ¼ 7)
1.00 (0.01)
1.02 (0.01)
Indoor, AL & SC (n ¼ 8)
0.98 (0.01)
1.00 (0.01)
Lake Ontario (n ¼ 15)
0.92 (0.02)
1.03(0.02)
Ambient, Columbia SC
(n ¼ 9)
0.99/1.02
(n ¼ 2)
–
1.51
(0.09)
Ambient, Muscle shoals,
AL (n ¼ 6)
0.98 (0.02)
(n ¼ 4)
20 Æ 19
(n ¼ 7)
1.70
(0.18)
Ambient, Point Petre, Lake
Ontario (n ¼ 8)
1.01 (0.05)
(n ¼ 6)
7.3 Æ 3.9
(n ¼ 7)
1.86
(0.05)
Ambient, Lake Superior
(n ¼ 6)
–
19 Æ 12
2.02
(0.10)
SOIL
Cornbelt region (n ¼ 38)
0.70 (0.12)
1.21 (0.14)
Alabama (n ¼ 9)
0.91 (0.05)
1.11 (0.10)
8.2 Transformation/Accumulation of Chiral Xenobiotics in Higher Organisms
189
Point on Lake Erie (0.034 ng/m
3 ). Ambient levels in two southern states were
somewhat higher at 0.109 ng/m
3 for rural Alabama and 0.295 ng/m
3 in the City of
Columbia, SC (Bidleman et al. 1998a, b, c, d). Average indoor air concentrations in
the Corn Belt states (16.7 ng/m
3 , n ¼ 20) were similar to average levels in homes in
Columbia (10.1 ng/m
3 , n ¼ 3) and rural Alabama (34.2 ng/m
3 , n ¼ 5).
Average enantiomeric ratios for trans- and cis-chlordane, heptachlor and heptachlor exoepoxide in air and soils from the Corn Belt region, South Carolina and
Alabama are summarised in Table 8.18.
Soils in the Corn Belt region show an enantiomeric difference for both trans- and
cis-chlordane: in the case of trans-chlordane, ER values less than 1.00 indicate the
preferential transformation of the (+)-enantiomer, while for cis-chlordane ER values
greater than 1.00 imply a preferential transformation of the (À)-enantiomer. A
comparison of enantiomeric ratios for Corn Belt soils and air-above soil samples
was carried out for six fields. The enantiomeric signatures of pesticides in the air
above the soil followed the same pattern as in the soil, both in direction of transformation and in relative magnitude. This preservation of ER profile on volatilisation is
in line with the results obtained for heptachlor, heptachlor exoepoxide and α-HCH
(Aigner et al. 1998; Bidleman et al. 1998a, b, c, d; Wiberg et al. 2001a, b). Chlordane
Table 8.18 Average enantiomeric ratios (ER ¼ (+)/(À)-enantiomer; Æ standard deviation) for
trans- and cis-chlordane, heptachlor and heptachlor exoepoxide in air and soil from the Corn Belt
region, South Carolina and Alabama (Aigner et al. 1998; Bidleman et al. 1998a, b, c, d)
Location
transChlordane
ER
cisChlordane
ER
Heptachlor
ER
Heptachlor exoepoxide Conc.
(pg/m
3
) ER
AIR
Above-soil, Cornbelt
(n ¼ 6)
0.74 (0.10)
1.11 (0.08)
Ambient, Cornbelt (n ¼ 3)
0.93 (0.03)
1.04 (0.04)
Indoor, Cornbelt (n ¼ 15)
0.99 (0.01)
0.98 (0.03)
Ambient, Alabama (n ¼ 20) 0.98 (0.03)
1.01 (0.04)
Ambient, SC (n ¼ 7)
1.00 (0.01)
1.02 (0.01)
Indoor, AL & SC (n ¼ 8)
0.98 (0.01)
1.00 (0.01)
Lake Ontario (n ¼ 15)
0.92 (0.02)
1.03(0.02)
Ambient, Columbia SC
(n ¼ 9)
0.99/1.02
(n ¼ 2)
–
1.51
(0.09)
Ambient, Muscle shoals,
AL (n ¼ 6)
0.98 (0.02)
(n ¼ 4)
20 Æ 19
(n ¼ 7)
1.70
(0.18)
Ambient, Point Petre, Lake
Ontario (n ¼ 8)
1.01 (0.05)
(n ¼ 6)
7.3 Æ 3.9
(n ¼ 7)
1.86
(0.05)
Ambient, Lake Superior
(n ¼ 6)
–
19 Æ 12
2.02
(0.10)
SOIL
Cornbelt region (n ¼ 38)
0.70 (0.12)
1.21 (0.14)
Alabama (n ¼ 9)
0.91 (0.05)
1.11 (0.10)
8.2 Transformation/Accumulation of Chiral Xenobiotics in Higher Organisms
189