Industrial pollution I reckon. A lot of industrial waste is discharged completely untreated directly into rivers and the sea or discharged into the soil, not to mention the air pollution. Heavy metals stick around in the soil and water for ages and accumulate in plants and animals, which are then eaten by humans. Foetuses are very sensitive to heavy metals and other pollutants, levels that can cause birth defects don't necessarily produce noticeable symptoms in adults, at least initially. One (of many) such examples are a lot of "artisan" or small time leather tanners that just tip the used tanning solution, containing shit like hexavalent chromium, into rivers used for irrigation, bathing or drinking. It pollutes the soil, water, plants, livestock, wild animals, everything. This is repeated all over the country. Even large companies are guilty of doing shit like this, they don't do it in more developed countries, but they can get away with it there and it saves them money, so they do.
good reply. but now I'm wondering is there anything that can help undo the amount of chemicals and heavy metals in the land and water or is it a lost cause