TABLE E5. 



INDUCTION OF SEX-LINKED RECESSIVE LETHAL MUTATIONS IN DROSOPHILA BY 



NITROFURANTOIN (a) 



(a) Study performed at Bowling Green State University. A detailed protocol of the se.x-linked recessive lethal assay is presented 

 in Zimmering et al. (1985). I Exposure by feeding was done by allowing 24- hour-old Canton-S males to feed for 3 days on a solu- 

 tion of the study chemical dissolved in 5% sucrose. In the mjection experiments, 24-hour-old Canton-S males were treated with 

 a solution of the chemical dissolved in 0.7% saline and allowed 24 hours to recover. I Exposed males were mated to three Base fe- 

 males for 3 days and given fresh females at 2-day intervals to produce three broods of 3, 2, and 2 days; sample sperm from suc- 

 cessive matings were treated as spermatozoa (mating 1 ), spermatids (mating 2), and spermatocytes (mating 3 1. F[ heterozygous 

 females were crossed to their siblings and placed ui individual vials. Fj daughters from the same parental male were kept to- 

 gether to identify clusters; no clusters were found. After 17 days, presumptive lethal mutations were identified as vials con- 

 taining no wild- type males; these were re tested. Results were notsignificant at the 5% level (Margolin et al., 1983). 



(b) Combined total of number of lethal mutations/number of X chromosomes tested for three mating trials 



199 



Nitrofurantoin, NTP TR 341 



