Imiprothrin

SECTION 2: Hazards identification

CHEMWATCH HAZARD RATINGS Min Max Flammability: 1 Toxicity: 2 Body Contact: 2 Min/Nil=0 Low=1 Reactivity: 1 CANADIAN WHMIS SYMBOLS 1 of 9 EMERGENCY OVERVIEW RISK Harmful by inhalation, in contact with skin and if swallowed. Very toxic to aquatic organisms, may cause long-term adverse effects in the aquatic environment.

Potential Acute Health Effects

SWALLOWED Accidental ingestion of the material may be harmful; animal experiments indicate that ingestion of less than 150 gram may be fatal or may produce serious damage to the health of the individual. Limited evidence exists that the substance may cause irreversible but non-lethal mutagenic effects following a single exposure. Ingestion of pyrethrins may produce nausea, vomiting, headache and other central nervous system disturbances. Excitation, muscular tremors and a period of shock may be followed by death. EYE Although the liquid is not thought to be an irritant, direct contact with the eye may produce transient discomfort characterized by tearing or conjunctival redness (as with windburn). SKIN Skin contact with the material may be harmful; systemic effects may resultfollowing absorption. The liquid may be miscible with fats or oils and may degrease the skin, producing a skin reaction described as non-allergic contact dermatitis. The material is unlikely to produce an irritant dermatitis as described in EC Directives . Skin contact with natural pyrethrins may result in severe dermatitis and may also be associated with allergic rhinitis and asthma. Absorption through the skin may result in a toxic syndrome similar to that produced by inhalation. Open cuts, abraded or irritated skin should not be exposed to this material. Entry into the blood-stream, through, for example, cuts, abrasions or lesions, may produce systemic injury with harmful effects. Examine the skin prior to the use of the material and ensure that any external damage is suitably protected. INHALED Inhalation of vapors or aerosols (mists, fumes), generated by the material during the course of normal handling, may be harmful. The material is not thought to produce respiratory irritation (as classified using animal models). Nevertheless inhalation of vapors, fumes or aerosols, especially for prolonged periods, may produce respiratory discomfort and occasionally, distress. Inhalation of pyrethrins may produce nausea, vomiting, sneezing, serious nasal discharge, nasal stuffiness and asthma. High concentrations may produce hyperexcitability, incoordination, tremors, muscular paralysis and death (due to respiratory failure). This material, like natural pyrethrins, may cause central stimulation with nausea, vomiting, stomach upset, diarrhea, hypersensitivity, inco-ordination, tremors, muscle paralysis, convulsion, coma and respiratory failure. There may be aggressive behavior, tremor and weakness. Limited evidence exists that the substance may cause irreversible but non-lethal mutagenic effects following a single exposure.

Potential chronic health

Limited evidence suggests that repeated or long-term occupational exposure may produce cumulative health effects involving organs or biochemical systems. There is some evidence that inhaling this product is more likely to cause a sensitization reaction in some persons compared to the general population. There is limited evidence that, skin contact with this product is more likely to cause a sensitization reaction in some persons compared to the general population. Exposure to the material may result in a possible risk of irreversible effects. The material may produce mutagenic effects in man. This concern is raised, generally, on the basis of appropriate studies with similar materials using mammalian somatic cells in vivo. Such findings are often supported by positive results from in vitro mutagenicity studies. Chronic poisoning by natural pyrethrins may result in convulsion, tetanic paralysis, rapid and uneven heart beat, liver and kidney damage, or death. The natural pyrethrins may produce hypersensitivity, especially following previous sensitising exposure. In general, repeated exposures over 2 or 3 years are required to elicit a response and involve exposure to pyrethrum rather than its individual components (including pyrethrins). The sesquiterpene lactone (pyrethrosin) and the pyrethrum glycoproteins account for the immediate and delayed hypersensitivity seen in guinea pigs following a single injection of ground chrysanthemum in Freud's adjuvant. Mild erythematic vesicular dermatitis (with papules), pruritus, localized oedema (particularly of the face, lips and eyelids), rhinitis, tachycardia, pallor and sweating are the most common syndromes. An initial skin sensitisation can progress to marked dermal oedema and skin cracking. Pyrethrum dermatitis appears to increase in hot weather or under conditions were heavy perspiration is produced. The active ingredients of pyrethrum (except pyrethrin II) are inactive in patch tests. Those patients allergic to ragweed pollen are particularly sensitive to pyrethrin. Rats fed on a diet of pyrethrins for 5000 ppm for 2 years showed some signs of tissue damage including liver lesions, bile duct proliferation and focal necrosis of the liver cells. A no-effect level of 1000 ppm found in animal experiments correspond to a daily dose of 3600 mg/man. Based on the results of a developmental study in rabbits, imiprothin is not a developmental toxicant at dose levels which did not also produce maternal toxicity. Rats were fed imiprothrin at 30, 100 or 300 mg/kg body weight/ day. The maternal NOEL was 30 mg/kg/body weight based on suppressed 2 of 9 body weight gain and food consumption, while the LOEL was 100 mg/kg body weight/ day. At 300 mg/kg body weight/ day, premature labour, abortion, and mortality were noted. The developmental NOEL was not determined (i.e it is less than 100 mg/kg body weight/ day), on the basis of decreased foetal body weight and frontal bone hypoplasia. An increased incidence of the 27th pre-sacral vertebra occurred in all treatment groups. The LOEL was not determined. An additional developmental study was conducted on rabbits at doses of 3, 10 or 30 mg/kg body weight/ day to determine the developmental end points which the earlier study was not able to define. This study showed no treatment related developmental effects. the developmental NOEL, based on both studies was 30 mg/kg/day while the LOEL was 100 mg/kg/ body weight/ day. When subjected to the Ames test with Salmonella and with E. coli, imiprothin was not mutagenic. An in vitro gene mutation assay with Chinese hamster cells showed that this chemical does not have the potential to cause gene mutations. An in vitro chromosome aberration showed that imiprothrin did have the potential to cause chromosome aberrations in Chinese hamster lung cells in the presence of S9 metabolic activation. An in vivo mouse bone marrow micronucleus test did not show chromosome damage. Two in vivo/ in vitro unscheduled DNA synthesis test were conducted with primary rat hepatocytes; time course and dose response. Neither UDS test showed an increase in such synthesis. Th weight of evidence indicates that imiprothrin is not genotoxic.