Water Pollution and Its Control Questions in English

(D) The Water (Prevention and Control of Pollution) Act was enacted by the Parliament of India in $1974$ to provide for the prevention and control of water pollution and the maintaining or restoring of wholesomeness of water.

(B) The classification of water impurities is as follows:
$1$. Suspended solids $(P)$ include particles like sand, silt, and clay which are heavy and settle down easily. Thus, $(P-II)$.
$2$. Colloidal materials $(Q)$ include fine particles like fecal matter, bacteria, and cloth or paper fibers that remain suspended in water. Thus, $(Q-I)$.
$3$. Dissolved materials $(R)$ include substances that are completely dissolved in water, such as nutrients like nitrates, ammonia, phosphates, sodium, and calcium. Thus, $(R-III)$.
Therefore, the correct matching is $(P-II), (Q-I), (R-III)$.

(B) Domestic and hospital sewage contains various pathogenic microorganisms such as bacteria, viruses, and protozoa.
These pathogens are responsible for water-borne diseases when untreated sewage is released into water bodies.
$I-$ Dysentery and $II-$ Diarrhoea are caused by protozoans and bacteria found in sewage.
$II-$ Typhoid is caused by the bacterium $Salmonella \text{ } typhi$.
$III-$ Hepatitis (specifically Hepatitis $A$) is a viral disease transmitted through contaminated water.
$V-$ Cholera is caused by the bacterium $Vibrio \text{ } cholerae$.
$IV-$ Cancer is not a water-borne infectious disease caused by pathogens in sewage.
$VI-$ $AIDS$ is caused by the $HIV$ virus, which is not transmitted through water-borne routes from sewage.
Therefore, the diseases caused by water-borne pathogens from sewage are $I, II, III,$ and $V$.

(D) Industrial effluents are a major source of water pollution.
Industries such as petroleum refineries,paper and pulp mills,metal extraction and processing units,and chemical manufacturing plants release significant amounts of toxic substances and heavy metals (such as mercury,lead,cadmium,and chromium) into water bodies.
These pollutants are non-biodegradable and can cause severe health issues through bioaccumulation and biomagnification.
Therefore,all the listed industries contribute to this type of pollution.