Nke mbụ, ndị na-emepụta ihe na-enweta aotutu iberibenangwongwo ndị nwere nkwarụsite na ụlọ ọrụ akpụkpọ anụ na ọnụ ahịa dị oke ala, na mgbe ahụgbanye ihe ndị a na mmiri nnu dị oke elu, ka o wee zereire ere n'oge nchekwa. Mgbe akpụkpọ ahụ rutere n'ebe a na-emepụta nri nri, a na-etinye ya na kemịkalụ ma were wayo ekewapụ abụba na akpụkpọ ahụ, wee gwọọ ya.kemịkalụ ndị ọzọ iji gwọọ ntutu isi, mgbe ahụrinsed ọzọ, ọzọ na-enweghị chemicals.