Teflubenzuron

Toxicity to birds

Additional information

Reliable information on the short-term (acute) toxicity of the test item to birds is available. No information on the long-term (chronic) toxicity to birds is available.

Two valid GLP-compliant guideline studies on the acute oral toxicity of the test item to birds are available and summarized below. Both studies were submitted in the EU and are summarized in the original Draft Assessment Report (DAR) for teflubenzuron in accordance to the Council Directive 91/414/EEC (2007) and the Addendum to the DAR (November 2002).

  

Supporting information

Huntington Research Centre (1987): The Acute Oral Toxicity (LD₅₀) of CME 134 to the Mallard Duck. Un­published report, report No. FCC 99/851578,  according to Draft Assessment Report (2007) according to Council Directive 91/414/EEC, crossreference MCA 8.1.1/01

An acute oral toxicity test according to Guideline US EPA/FIFRA No. 71-1 (1983) was carried out to investigate the acute toxic effects of teflubenzuron (CME 134) in the Mallard duck (Anas platyrhynchos).

40 male and 40 female birds (Anas platyrhynchos) with an age over 16 weeks and with a bodyweight of 840–1250 g were obtained. 24 male and 24 female birds were used in the study (2 for the range-finding test, 40 in the main study, 6 for use as possible replacements). The birds were housed in pens of galvanised steel measuring 1.5 x 1.2 m with wire mesh floors. Temperatures and relative humidity were recorded daily throughout the study. The photoperiod was 7/17 hours light/dark, ventilation fans were adjusted, as necessary. The birds were offered a standard diet in pellet form, which was known to contain no antibiotics or growth promot­ers. Water was available all the time and feed was offered ad libitum (except an overnight starvation period prior to dosing). The birds could be identified by numbered metal wing tags. The test compound was administered in suspension in corn oil. The concentra­tions were calculated to give a dose volume of 5 mL suspension/kg body weight at all dose levels. Single doses were given by oral gavage on Day 0.

The duration of the study was 28 days (14 days pre-treatment period and 14 days post-treatment period). The bird’s health and mortalities were observed daily. Body weights were recorded on days -14, -7, 0 (immediately prior to dos­ing), 7 and 14. The group mean feed consumptions were recorded weekly over the period’s days -14 to -8, -7 to 0, 0 to 7 and 8 to 14. Birds that died during the study and all birds from the high dose level group at test termination were examined for gross pathological changes.

The mean maximum temperature was 17°C (15–20 °C), the mean minimum temperature was 13 °C (10–17 °C) and the average relative humidity was 79 % (70–92 %). No signs of toxicity were observed and all birds remained in good health throughout the study. Since there were no mortalities following dosing, it was not possible to deter­mine an LD₅₀ value, which must be in excess of 2000 mg a.s./kg bw. Between days –14 and 0, birds in all groups tended to decrease in weight. Fol­lowing dosing, bodyweight was very variable, but overall, weight increases over days 0–14.There was no evidence of any treatment-related effect. Feed consumption data were variable but were considered to be within normal limits in all groups. With exception of the bird, which was sacrificed on day –7, no abnormalities were detected in any of the birds examined.

There was no evidence of any treatment related effects of the test item on health, body weight and feed consumption of mallard duck at any of the dose levels up to 2000 mg a.s./kg body weight. Therefore, a LD₅₀ could not be calcu­lated; this value is greater than 2000 mg a.s./kg body weight, which was the highest dosage level tested.

 

Wildlife International (1984): An Acute Oral Toxicity Study in the Bobwhite with CME-134. Unpublished report, report No. 146-106, according to Draft Assessment Report according to Council Directive 91/414/EEC, crossreference MCA 8.1.1/02

An acute oral toxicity test according to Guideline US EPA/FIFRA No. 71-1 (1982) was carried out to investigate the acute toxic effects of teflubenzuron (CME 134) in the bobwhite quail (Colinus virginianus). Apparently healthy, pen-reared, mature bobwhite quail, approximately five months old, were examined for physical injury and acclimated for at least 14 days. Groups of 10 bobwhite quail (5 male and 5 female) were distributed by random draw to each of the 5 treatment groups and the control group. 15 hours prior to dosing, feeding was stopped. Nominal dosages used in this study were 292, 486, 810, 1350 und 2250 mg a.s./kg body weight. The test substance was dispersed in corn oil and intubated into the crop via a stainless steel catheter. Each bird was weighed and dosed on the basis of mg a.s./kg body weight. The control birds received corn oil only. The concentration of test substance was adjusted to receive a constant volume to body weight dose. Feed (diet) and water were available ad libitum following dosage. The birds were housed indoors by treatment in modified Georgia Quail Farm Breeder units. Each pen measured 78 x 51 x 23 cm. The average temperature for the study was 25 ± 2 °C with an average relative humidity of 74 %. The photoperiod was 8/16 hours light/dark. All birds were observed daily and a record was maintained of all mortalities and/or signs of toxicity and abnormal behaviour. The LD₅₀ value was deter­mined by inspection. Body weights were recorded by groups on days 0, 3, 7 and 14. Feed consumption was measured for days 0–3, 4–7 and 8–14. Feed consump­tion was measured accurately, but is presented as an estimate due to the unavoidable wastage by the birds.

There were no mortalities, signs of toxicity or abnormal behaviour throughout the test. All birds were normal in appearance and behav­iour throughout the test. There was no effect on body weight or feed consumption at any dosage tested. There was no evidence of any treatment related effects by the test item on health, body weight and feed consumption of bobwhite quail at any of the dose levels up to 2250 mg a.s./kg body weight. Therefore, a LD₅₀ could not be calcu­lated; this value was greater than 2250 mg a.s./kg body weight, which was the highest dosage tested.

 

Conclusion

In an avian acute oral toxicity test with Anas platyrhynchos according to Guideline US EPA/FIFRA No. 71-1 (1983) the 14-day LD50 of the test item was determined to be > 2000 mg a.s./kg bw. In a second avian acute oral toxicity test with Colinus virginianus according to Guideline US EPA/FIFRA No. 71-1 (1982) the 14-day LD50 of the test item was determined to be > 2250 mg a.s./kg bw.