Avermectin B1a

SECTION 2: Hazards identification

CHEMWATCH HAZARD RATINGS Min Max Flammability: 1 Toxicity: 4 Body Contact: 3 Min/Nil=0 Low=1 Reactivity: 1 Moderate=2 High=3 Chronic: 2 Extreme=4 CANADIAN

Potential Acute Health Effects

SWALLOWED ■ Severely toxic effects may result from the accidental ingestion of the material; animal experiments indicate that ingestion of less than 5 gram may be fatal or may produce serious damage to the health of the individual. ■ In humans, exposure to abamectin (a mixture of avermectins) has caused fever, rash, lymph node swelling, dilated pupils, sedation, vomiting, tremors, convulsions, coma and death. Eye reactions have been minimal. ■ Macrolides are antibiotics derived from bacteria. They most commonly cause gastrointestinal discomfort but rarely cause supra-infection, allergic sensitisation, watery eyes, shortness of breath, nasal congestion, choking, coughing and wheezing. EYE ■ Although the material is not thought to be an irritant (as classified by EC Directives), direct contact with the eye may cause transient discomfort characterised by tearing or conjunctival redness (as with windburn). Slight abrasive damage may also result. SKIN ■ Skin contact with the material may produce toxic effects; systemic effects may result following absorption. ■ The material is not thought to be a skin irritant (as classified by EC Directives using animal models). Abrasive damage however, may result from prolonged exposures. ■ In rats and rabbits, skin exposure to abamectin under occluded conditions produced tremors, unsteady gait, decreased activity, weight loss and death. ■ 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 dusts, generated by the material, during the course of normal handling, may produce severely toxic effects; these may be fatal. ■ The material is not thought to produce respiratory irritation (as classified by EC Directives using animal models). Nevertheless inhalation of dusts, or fumes, especially for prolonged periods, may produce respiratory discomfort and occasionally, distress. ■ Persons with impaired respiratory function, airway diseases and conditions such as emphysema or chronic bronchitis, may incur further disability if excessive concentrations of particulate are inhaled. If prior damage to the circulatory or nervous systems has occurred or if kidney damage has been sustained, proper screenings should be conducted on individuals who may be exposed to further risk if handling and use of the material result in excessive exposures. ■ There were no deaths recorded in rats inhaling 5. 73 mg/l avermectins; the animals also exhibited normal behaviour and there were no changes in body weights.

Potential chronic health

Substance accumulation, in the human body, is likely and may cause some concern following repeated or long-term occupational exposure. Long term exposure to high dust concentrations may cause changes in lung function i.e. pneumoconiosis; caused by particles less than 0.5 micron penetrating and remaining in the lung. Prime symptom is breathlessness; lung shadows show on X-ray.