DL-threo-Dihydrosphingosine

SECTION 2: Hazards identification

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

Potential Acute Health Effects

SWALLOWED The material has NOT been classified as "harmful by ingestion". This is because of the lack of corroborating animal or human evidence. EYE Although the material is not thought to be an irritant, direct contact with the eye may cause transient discomfort characterized by tearing or conjunctival redness (as with windburn). Slight abrasive damage may also result. SKIN The material is not thought to produce adverse health effects or skin irritation following contact (as classified using animal models). Nevertheless, good hygiene practice requires that exposure be kept to a minimum and that suitable gloves be used in an occupational setting. 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 The material is not thought to produce adverse health effects or irritation of the respiratory tract (as classified using animal models). Nevertheless, good hygiene practice requires that exposure be kept to a minimum and that suitable control measures be used in an occupational setting. 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.

Potential chronic health

Limited evidence suggests that repeated or long-term occupational exposure may produce cumulative health effects involving organs or biochemical systems. 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. The material may inhibit protein kinase. This family of kinases enzymatically catalyses the phosphorylation of protein . Because phosphorylation triggers a signaling cascade which in turn produces cell growth, inhibition effectively retards the process. There are several different inhibitors which act in this manner but most common are genistein (a naturally occurring steroid-like substance from soybeans), lavendustin (a microbial metabolite) and the tyrphostins (synthetic analogues). Two families of protein kinase have been identified; serine-threonine kinases (also known as PKC) require calcium ion for their activation. The activated PKC phosphorylates proteins of the cellular signal cascade, which eventually induce expression of growth regulatory genes. tyrosine kinases which similarly regulate signal transmission to growth regulatory genes Inhibition may suppress cell or tissue growth or development.