Which is NOT a common chemical parameter tested in routine chemical analysis?

Fluoride is not typically included in the routine chemical analysis for water quality or environmental assessments. The primary purpose of routine chemical testing is to evaluate common contaminants and constituents that are more frequently encountered in water samples, particularly in rural or urban settings. Chlorides, nitrites, and sulphates are closely monitored due to their implications on health and the environment, including their roles in pollution, nutrient loading, and potential toxicity.

Chlorides are important for assessing salinity and potential sources of pollution, nitrites are critical for evaluating water quality, especially in relation to agricultural runoff and possible health risks, and sulphates are relevant for understanding the presence of acid rain or industrial impacts. In contrast, fluoride is generally analyzed in more specialized contexts, especially in water systems where fluoride levels are strictly regulated due to its association with dental health. Thus, while fluoride can be important, it is less commonly tested in standard routines compared to the other parameters listed.