Toxic inorganic anions

Results of the EDAR index application to these types of matrices are provided in Table 5. Samples were selected for toxicity screening to ensure the presence of different types of contaminants commonly present in complex wastes (e.g., hydrocarbons, DOC, nutrients, ammonia, inorganic anions and cations, pesticides) and other matrices (e.g., sediments and sludges, solid materials, liquid... 

The direct and indirect toxicity and genotoxicity of particulate matter after its ingestion or inhalation by humans is determined by its physical features such as size, number and surface area of particles, but also by their chemical composition. Elemental carbon and inorganic anions like sulphate and nitrate seem to be the... 

Besides the common inorganic anions (F , CU, Br, NOa , P04 , and S04 ) and cations (Na, K, NH4", Mg " ", and Ca " "), chromate and arsenite are of primary concern because of their greater toxicides as compared to chromium(III) and arsenate, respectively. Hexavalent chromium is a toxic form of chromium that must be monitored in manufacturing wastes. Ion chromatography with postcolumn addition of diphenylcarbazide is probably the most specific and sensitive method available for the determination of hexavalent chromium. 

In food, drinking water and drinks there are numerous inorganic anions. Some anions are forms of organogenic elements (such as carbonates and hydrogen carbonates), of essential elements (chlorides, phosphates, sulfates, iodides, fluorides, borates) and of non-essential elements (bromides). These and many other anions are mostly beneficial or harmless, and toxic effects exhibit only if present in food, drinking water and drinks in large quantities. Toxic effects can also result from an excessive accidental intake of these anions (fluorides, iodides and bromides). 

In the area of municipal and iadustrial wastewater treatment, the principal environmental issue is the toxicity of residual flocculating agents ia the effluent. Laboratory studies have shown that cationic polymers are toxic to fish because of the iateraction of these polymers with giU. membranes. Nonionic and anionic polymers show no toxicity (82,83). Other studies have shown that ia natural systems the suspended inorganic matter and humic substances substantially reduce the toxicity of added cationic polymer, and the polymers have been used successfully ia fish hatcheries (84—86). Based on these results, the EPA has added a protocol for testing these polymers for toxicity toward fish ia the presence of humic acids (87). The addition of anionic polymers to effluent streams containing cationic polymers to reduce their toxicity has been mentioned ia the patent Hterature (83). 

Kit solution for the determination of toxic anions (e.g., arsenate, arsenite, azide, or cyanide) and other inorganic and organic anions with indirect UV detection... 

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