___ Table 5. Ratio of storage in earthworms to exposure from soils at various times since application.* 

Time a. DDT plots Heptachlor plots 
Year since Dieldrin DDE + Heptachlors 
and application _ plots _ DDD + DDD + Heptachlor y- and 
month (months) Dieldrin p,p'-DDT  p,p-DDE DDT DDT Heptachlor epoxide — chlordane _chlordanes 
1966 
May 0.1 34.3 ¢ 2.2 b 248.8b 17.5ab 19.7ab 1.7 be 1,879.0a 21.1be 12.5 bede 
June 0.5 30.9 ¢ 5.0ab 401.2a 24.5ab 29.7ab 43a 132.1b 31.5b — 18.8 be 
June 1.0 63.5 be 12.3a 65.7¢ 26.9 ab 28.0ab 216 26.6b 15.0 be 11.7 bede 
July 2.0 100.7 b 7.5ab 120.5be 43.3a 47.2a 1.7 be 43.2b 286b 21.3b 
Sept. 4.0 166.4 a 3.7b 44.0c¢ 27.5ab 312ab  1.7be 46.7b 75.6a 38.0a 
Nov. 6.0 11.2c l1b 14.9¢c 45b 5.5b 0.15 cd 10.2b 16.9be 8.9 cde 
1967 
Jan. 8.0 5.5¢ 0.32 b le 31b 40b 0.03 d 96b lllbe 84de 
March 10.0 13.9¢ 0.22 b %5¢e 43b 5.9b 1.1 bed 18.5b 18.0be 16.1 bed 
May 12.0 22.8 ¢ 0.41 b 30.9¢ 12.3ab 14.4b 0.0d 20.7b 21.3be 16.3 bed 
Sept. 16.0 11.7¢ 5.5 ab 21.6c 83b 10.5b 0.0d 16.8b 10.0be 10.2 cde 
1968 
Jan. 20.0 5.3¢ 0.16 b lW.5c 18b 26b 0.0d 41b 26c 2.8e 
May 24.0 ll.5c 0.28 b W7c¢ 53b £646 0.0d 13.6b 19.1 be 12.7 bede 
aStorage: Exposure ratio is calculated by dividing the ppm (dry weight) in earthworms by the ppm (dry weight) in soils. Means that do 
not share a common letter are significantly different. 
study (Korschgen 1970, 1971). Our maximum ratios also DDT Plots 
corresponded to those periods of peak earthworm residues. 
In an Illinois study (Luckmann and Decker 1960), diel- 
drin levels in soils and earthworms from fields treated 
from 1 to 5 years before sampling decreased with time. 
However, no seasonal influences could be evaluated due to 
the sampling scheme. 
Two subsamples of the wettable powder formulation of 
“50%” technical DDT averaged 43.2% active ingredients: 
35.2% p,p'-DDT, 7.5% o,p'-DDT, 0.4% o,p'-DDD, 
0.1% o0,p'-DDE, and no p,p'-DDD, or p,p'-DDE. The 
principal residues in the plots were p,p'-DDE, p,p'-DDD, 
Table 6. Time relation between environmental factors and residues in soil and earthworms.* 




Mean amounts in soils Mean amounts in earthworms 
Time since Rainfall 2 weeks Percent 
application before sampling Percent organic Percent Percent 
Year and month (months) (inches) moisture matter pH moisture lipids 
1966 
May 0.1 0.00 17.67 ed 3.50 ced 6.7le 71.24 de 0.431 h 
June 0.5 0.41 17.17 ed 3.63 ed 7.10 c¢ 71.99 d 1.019 be 
June 1.0 0.73 13.69 e 3.16 d 6.78 de 70.82 de 1,126 b 
July 2.0 0.20 8.08 g 3.91 abed 6.89 d 78.67 a 0.806 e 
Sept. 4.0 7,00 17.94 ¢ 3.82 abcd 6.72 e 74.13 ¢ 0.605 fg 
Nov. 6.0 0.47 16.97 ed 3.81 abed 6.78 de 71.06 de 0.529 gh 
1967 
Jan. 8.0 0.41 19.78 b 4.59 a 7.23 be 70.89 de 0.666 f 
March 10.0 1.28 20.49 b 3.24 d 7.09 ¢ 70.53 e 0.958 ed 
May 12.0 1,25 15.87 d 3.64 bed 6.91 d 71.88 d 0.936 cde 
Sept. 16.0 0.20 11.61 f 4.56 a 7.41 a 75.63 b 0.859 de 
1968 
Jan. 20.0 2.26 27.03 a 4.15 abe 7.30 ab 73.42 ¢ 0.846 de 
May 24.0 1.75 20.85 b 4.47 ab 7.lle 76.28 b 1,308 a 
Average _ — 17.26 3.87 7.00 73.05 0.841 
4Means that do not share a common letter are significantly different. 



