Toxicity rating

Lanthanum and its compounds have a low to moderate acute toxicity rating therefore, care should be taken in handling them. 

Neodymium has a low-to-moderate acute toxic rating. As with other rare earths, neodymium should be handled with care. 

Pure holmium has a metallic to bright silver luster. It is relatively soft and malleable, and is stable in dry air at room temperature, but rapidly oxidizes in moist air and at elevated temperatures. The metal has unusual magnetic properties. Few uses have yet been found for the element. The element, as with other rare earths, seems to have a low acute toxic rating. 

Poly(vinyl alcohol) has a low oral toxicity rating. The oral LD q is higher than 10,000 mg/kg (rats). Concentrations of up to 10,000 mg/L in water were tested for toxicity to bluegik sunfish. No mortaUty or response indicative of intoxication was observed (283). 

In general the lanthanides, including cerium, have a low toxicity rating (17), especially when they are present in material having low aqueous solubiUty. When orally adrninistered poor absorption from the gastrointestinal tract tends to result in the lanthanides generally having Httle effect. The anion is often an important deterrninant in toxicity. 

Animal acute oral LD q, g/kg Toxicity rating Probable lethal oral dose for 70 kg person, g ... 

Toxicity rating Commonly used term LDso Single oral dose for rats (g/kg) 4hr Vapour exposure causing 2 to 4 deaths in 6-rat group (ppm) LDso Skin for rabbits (g/kg) Probable lethal dose for humans... 

Gupta PK, Murthy RC, Chandra SV. 1981. Toxicity of endosulfan and manganese chloride Cumulative toxicity rating. Toxicol Lett 7 221-227. 

Toxicity rating Toxicity term LDso (oral, rat) mg/kg Likely LD for humans... 

LCtS0 (percutaneous) ICtgo (respiratory) ICtgo (percutaneous) Rate of detoxification Skin and eye toxicity Rate of action Overexposure effects... 

Skin and eye toxicity Rate of action Overexposure effects... 

The problem of toxic pollutants is difficult to handle because of the great variety of chemicals involved. They represent a hazard not only to aquatic life, but also to human health, either through direct exposure or indirectly through consumption of contaminated fish or waterfowl. The degree of hazard depends on the pollutanf s toxicity, rate of discharge, persistence and distribution in the aquatic system, and bioaccumulation potential. Some highly volatile compounds, when discharged into water, evaporate and become air pollutants. 

More than one method was used to evaluate the toxicities of the hydrocarbons. The first was to give a toxicity rating to each hydrocarbon based on the speed and com-... 

Toxicity rating 1 = no toxicity 9 = complete, rapid kill. 

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