ToxicologyLetters, 64/65 (1992) 779-781 0 1992 Elsevier Science Publishers B.V., All rights reserved 03784274/92/$5.00
779
Three-generation reproductive studies of a synthetic pyrethroid - cyhalothrin P.B. Deshmukh Jai Research Foundation, Gyiarat (India) Key words: Cyhalothrin; Pyrethroid; Reproduction
SUMMARY The present study was carried out to understand the effect of cyhalothrin, a synthetic pyrethroid, on reproduction in mice. The study was designed as a three-generation reproduction study. Mice were given 2.5 and 5.0 ppm cyhalothrinkg body weight orally. Daily cumulative body weight of the pregnant mice, number of pups, and cumulative body weight of pups were noted during the study. Compared with the control, body weight gain of cyhalothrintreated parent mice of the first generation (for both concentrations) was less. As per Dunnet t-test, the weights of treated mice were comparable with control or were statistically nonsignificant. The other two generations did not show significant changes in body weight gain. Cyhalothrin fed orally did not affect the body weight gain of the pups in any of the generations. There was no significant difference in the viability index in any of the generations. Survival of the pups of dams given cyhalothrin was similar to that in the control.
INTRODUCTION
Cyhalothrin is a synthetic pyrethroid insecticide. Although toxicity data on acute, subacute and other toxicological parameters are available, no information is available on the reproductive toxicological parameters. The present study was planned to understand the effect of cyhalothrin on reproduction in mice, The experiment was designed as a three-generation reproduction study to evaluate effects of cyhalothrin on mating, fertility, pregnancy, lactation, litter size, litter survival, male/female sex ratio, body weight gain, food consumption and progeny’s reproductive performance.
Correspondence to: P.B. Deshmukh, Jai Research Foundation, Off N.H. No. 8, P.O. Valvada, District Valsad, Gujarat, India.
100
52.91
47.08
9.33 21.42
50.89
48.10
8.00 f1.70
47.88
52.11
9.75 kO.88
100
100
100
100
100
100
100
55.68
44.31
9.75 t1.02
61.93
38.06
7.00 51.58
100
100
100
100
100
100
12.33
20.00
12.33 k1.58
T2
100
100
11.45
18.25
11.45 k1.02
Tl
*Mean 2 S.E.; *+ Mean + S.E. (mean number of litter from 6 mothers). C = Control; Tl = Cyhalothrin 2.5 ppm dose; T2 = Cyhalothrin 5.0 ppm dose.
44.05
55.94
Female
9.33 il.68
Male
Male/female ratio
Litter size* *
100
100
100
100
100
100
Male fertility index 100 (%) Pups live birth index 100 (%) Pups 4-day survival 100 index (%)
Pups Zl-day survival 100 index (%)
100
100
100
10.70
13.97
12.09
12.38
100
Female fertility index (%)
18.50
18.00
18.16
10.70 20.88
C
17.37
Body weight gain in gestating females (g., Body weight gain in offspring (g)
T2 13.97 il.70
Tl
Generation 2
12.09 k1.42
12.38 k1.68
C
Generation 1
Feed consumption (g/day/animal)*
Particulars
EFFECT OF CYHALOTHRIN ON REPRODUCTIVE FUNCTIONS IN MICE
TABLE I
30.90
69.09
5.33 fO.91
100
100
100
100
100
9.17
14.66
12.33 21.58
C
47.61
52.38
5.66 +2.02
100
100
100
100
100
14.29
16.34
9.17 to.91
Tl
Generation 3
53.70
46.29
7.00 to.86
100
100
100
100
100
11.52
14.34
14.29 22.02
T2
781
MATERIALS AND METHODS
Cyhalothrin was obtained as a free gift from M/s United Phosphorus Ltd., Bombay (India). The sample was a colourless liquid (specific gravity 0.9071). Albino Swiss mice (45 days old) were obtained from the mice colony of Jai Research Foundation. Sixteen male (21-25 g) and 32 female (21-25 g) mice were obtained and divided in 4 groups; each group consisted of 4 males and 8 females. They were caged for mating 1:2 (male:female) ratio. The mice were administered oral doses of 0 (blank control), 2.5 ppm and 5.0 ppm cyhalothrin&g body weight daily. Standard mice feed and drinking water was given ad libitum throughout the study period. The three-generation data obtained was assessed as per Dixon Cl]. RESULTS AND DISCUSSION
Mice administered cyhalothrin by the oral route did not show any symptoms or behavioural changes in the sires, dams and pups throughout the test period and for up to three generations. The body weight of gestating females and pups of all three generations who were given cyhalothrin orally did not differ significantly from the control, except on day 1, pups’ body weight of F2 generation at 5 ppm cyhalothrin dose level. The food consumption of cyhalothrin-treated gestating females of generation 1 and 2 did not differ significantly from the control. However, in generation 3 gestating females with a 2.5 ppm dose level, a significant increase in food consumption was observed which could not be explained. No dose-related significant difference was observed in mice treated with cyhalothrin (2.5 and 5.0 ppm) for 3 generations on the following parameters: male and female fertility indices, pups live birth and pup survival indices, litter, size, or sex ratio (Table I). Overall, it appears that cyhalothrin 3 generation treatment with 2.5 and 5.0 ppm dose did not alter the reproductive parameters or performances in mice. However, the study should involve more species of animals, either to confirm or refute the present studies. REFERENCES 1
Dixon, P.L. (1980) Toxic responses of the reproductive system. In: J. Doull, C.D. Klaassen and M.O. Amdur (Eds.), Casarett and Doull’s Toxicology. Macmillan Publishing Co. Inc., New York, pp. 332-354.
779
Three-generation reproductive studies of a synthetic pyrethroid - cyhalothrin P.B. Deshmukh Jai Research Foundation, Gyiarat (India) Key words: Cyhalothrin; Pyrethroid; Reproduction
SUMMARY The present study was carried out to understand the effect of cyhalothrin, a synthetic pyrethroid, on reproduction in mice. The study was designed as a three-generation reproduction study. Mice were given 2.5 and 5.0 ppm cyhalothrinkg body weight orally. Daily cumulative body weight of the pregnant mice, number of pups, and cumulative body weight of pups were noted during the study. Compared with the control, body weight gain of cyhalothrintreated parent mice of the first generation (for both concentrations) was less. As per Dunnet t-test, the weights of treated mice were comparable with control or were statistically nonsignificant. The other two generations did not show significant changes in body weight gain. Cyhalothrin fed orally did not affect the body weight gain of the pups in any of the generations. There was no significant difference in the viability index in any of the generations. Survival of the pups of dams given cyhalothrin was similar to that in the control.
INTRODUCTION
Cyhalothrin is a synthetic pyrethroid insecticide. Although toxicity data on acute, subacute and other toxicological parameters are available, no information is available on the reproductive toxicological parameters. The present study was planned to understand the effect of cyhalothrin on reproduction in mice, The experiment was designed as a three-generation reproduction study to evaluate effects of cyhalothrin on mating, fertility, pregnancy, lactation, litter size, litter survival, male/female sex ratio, body weight gain, food consumption and progeny’s reproductive performance.
Correspondence to: P.B. Deshmukh, Jai Research Foundation, Off N.H. No. 8, P.O. Valvada, District Valsad, Gujarat, India.
100
52.91
47.08
9.33 21.42
50.89
48.10
8.00 f1.70
47.88
52.11
9.75 kO.88
100
100
100
100
100
100
100
55.68
44.31
9.75 t1.02
61.93
38.06
7.00 51.58
100
100
100
100
100
100
12.33
20.00
12.33 k1.58
T2
100
100
11.45
18.25
11.45 k1.02
Tl
*Mean 2 S.E.; *+ Mean + S.E. (mean number of litter from 6 mothers). C = Control; Tl = Cyhalothrin 2.5 ppm dose; T2 = Cyhalothrin 5.0 ppm dose.
44.05
55.94
Female
9.33 il.68
Male
Male/female ratio
Litter size* *
100
100
100
100
100
100
Male fertility index 100 (%) Pups live birth index 100 (%) Pups 4-day survival 100 index (%)
Pups Zl-day survival 100 index (%)
100
100
100
10.70
13.97
12.09
12.38
100
Female fertility index (%)
18.50
18.00
18.16
10.70 20.88
C
17.37
Body weight gain in gestating females (g., Body weight gain in offspring (g)
T2 13.97 il.70
Tl
Generation 2
12.09 k1.42
12.38 k1.68
C
Generation 1
Feed consumption (g/day/animal)*
Particulars
EFFECT OF CYHALOTHRIN ON REPRODUCTIVE FUNCTIONS IN MICE
TABLE I
30.90
69.09
5.33 fO.91
100
100
100
100
100
9.17
14.66
12.33 21.58
C
47.61
52.38
5.66 +2.02
100
100
100
100
100
14.29
16.34
9.17 to.91
Tl
Generation 3
53.70
46.29
7.00 to.86
100
100
100
100
100
11.52
14.34
14.29 22.02
T2
781
MATERIALS AND METHODS
Cyhalothrin was obtained as a free gift from M/s United Phosphorus Ltd., Bombay (India). The sample was a colourless liquid (specific gravity 0.9071). Albino Swiss mice (45 days old) were obtained from the mice colony of Jai Research Foundation. Sixteen male (21-25 g) and 32 female (21-25 g) mice were obtained and divided in 4 groups; each group consisted of 4 males and 8 females. They were caged for mating 1:2 (male:female) ratio. The mice were administered oral doses of 0 (blank control), 2.5 ppm and 5.0 ppm cyhalothrin&g body weight daily. Standard mice feed and drinking water was given ad libitum throughout the study period. The three-generation data obtained was assessed as per Dixon Cl]. RESULTS AND DISCUSSION
Mice administered cyhalothrin by the oral route did not show any symptoms or behavioural changes in the sires, dams and pups throughout the test period and for up to three generations. The body weight of gestating females and pups of all three generations who were given cyhalothrin orally did not differ significantly from the control, except on day 1, pups’ body weight of F2 generation at 5 ppm cyhalothrin dose level. The food consumption of cyhalothrin-treated gestating females of generation 1 and 2 did not differ significantly from the control. However, in generation 3 gestating females with a 2.5 ppm dose level, a significant increase in food consumption was observed which could not be explained. No dose-related significant difference was observed in mice treated with cyhalothrin (2.5 and 5.0 ppm) for 3 generations on the following parameters: male and female fertility indices, pups live birth and pup survival indices, litter, size, or sex ratio (Table I). Overall, it appears that cyhalothrin 3 generation treatment with 2.5 and 5.0 ppm dose did not alter the reproductive parameters or performances in mice. However, the study should involve more species of animals, either to confirm or refute the present studies. REFERENCES 1
Dixon, P.L. (1980) Toxic responses of the reproductive system. In: J. Doull, C.D. Klaassen and M.O. Amdur (Eds.), Casarett and Doull’s Toxicology. Macmillan Publishing Co. Inc., New York, pp. 332-354.
