A/68/264
infrastructure is common owing to the neglect of the need for operation and
maintenance (see A/HRC/24/44, paras. 4, 14, 16 and 22).
B.
Contamination from agriculture
35. Agriculture is the largest water user, accounting for about 70 per cent of global
water use, hence producing significant amounts of water polluted with pesticides
and fertilizers. It contributes to water pollution mainly as a non-point polluter:
residues of agricultural production percolate to groundwater aquifers and streams in
a manner that is extremely difficult to trace, quantify or regulate. 22 Moreover,
livestock rearing poses problems in terms of the disposal of faeces and urine high in
nitrate and phosphate, and partly pharmaceuticals. The Special Rapporteur found in
Costa Rica that the use of certain pesticides used in large-scale plantations has been
associated with cancer when leaching into groundwater (see A/HRC/12/24/Add.1,
para. 44). As in other sectors, patterns of inequalities emerge: in one country,
research revealed that communities housing high proportions of minority residents
are more likely to rely on water that has high levels of nitrates. 23 Such pollution
directly endangers the health of water users or indirectly threatens their livelihoods
and food supplies through the destruction of ecosystem services.
C.
Industrial water pollution
36. Industry is estimated to dispose of 300 million to 400 million tons (the weight
of the entire human population) of heavy metals, solvents, toxic sludge and other
waste into water bodies every year. 24 Industries that generate large amounts of
waste include mining, pulp mills, tanneries, sugar refineries and pharmaceuticals. 25
Mostly, industry is a point polluter, which in theory is easier to control and regulate.
However, it includes discharge from small-scale, partly informal industries, which
might be difficult to regulate in practice. In total, approximately 70 per cent of
industrial wastewater in developing countries remains untreated. 26
37. Water pollution can endanger access to safe drinking or irrigation water of
downstream users. Heavy metals also enter the food chain, thus putting at risk the
human rights to food and to health. 27 Often, water pollution concerns poorer
communities much more than others, as lack of infrastructure forces them to use
unsafe sources. In one city, wells and boreholes used by residents of a lower middle
class area have been shown to be polluted by cadmium and lead, with concomitant
health risks of cancer and kidney damage. 28
__________________
22
23
24
25
26
27
28
13-41825
Background discussion paper on wastewater, p. 5.
Carolina Balazs and others, “Social Disparities in Nitrate-Contaminated Drinking Water in
California’s San Joaquin Valley”, Environmental Health Perspectives, vol. 119, No. 9.
World Water Assessment Programme Water and Industry (2010).
Background discussion paper on wastewater.
UNESCO, United Nations World Water Development Report (third edition) (Paris, 2009).
Ibid., p. 139.
M. A. Momodu and C. A. Anyakora, “Heavy metal contamination of ground water: the Surulere
case study”, Research Journal Environmental and Earth Sciences, 2(1), pp. 39-43, University of
Lagos, Research Journal Environmental and Earth Sciences (2010).
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