Environmental Contamination by Industrial Effluents and Sludge Relative to Heavy Metals

Abstract

Oman is located in the tropic of Cancer with extremely hot temperatures ranging between 15˚C -25˚C in winter and 30 -48˚C in the summer with low rainfall. Most of the water source is desalinated seawater. Recycling of sewage effluent is a common practice used for farming, public parks and industry. The dried sludge product is used as fertilizer. The highly concentrated sludge with heavy metals is either incinerated or buried in landfills. Heavy metals were analyzed and compared in treated sewage effluent (TSE), slurry sludge, dried sludge, landfill and underground water. Heavy metal concentrations were analyzed using the inductive coupled plasma optical emission spectrometer (ICP-OES). All samples contained the same heavy metals with different concentrations. The heaviest concentrations were Zn, Cr, Cu and Ni with traces of V, Cd, Pb and Ba. TSE and sludge were the main sources of landfill and underground water contamination. Due to water evaporation, heavy metals concentrations in sludge were higher compared to TSE and underground water. Dried sludge and landfill contained higher concentrations than the others. Based on this investigation, it appears that the source of heavy metals is from TSE originated mainly in industries. If the infiltration of heavy metals to underground water continues, it will be a serious environmental and health problem in the future.

Análise da Conectividade dos Fragmentos na Bacia Hidrográfica do Tietê-Jacaré

“…No caso do gerenciamento de bacia hidrográficas, a questão sobre o comprometimento da qualidade da água para fins de abastecimento doméstico é decorrente de poluição por diferentes fontes, tais como efluentes domésticos, efluentes industriais e deflúvio superficial urbano e agrícola. Os efluentes domésticos, por exemplo, são constituídos basicamente por contaminantes orgânicos, nutrientes e microorganismos, que podem ser patogênicos (MERTEN;MINELLA, 2002;MUSHARAFI et al, 2014).…”

Heavy Metals in Sewage Treated Effluents: Pollution and Microbial Bioremediation from Arid Regions

“…This is a major problem in the developing countries [7,8]. Several major sources of heavy metal contamination which include consumer use of heavy metals, industrial waste, mining, and burning of fossil fuels leads to accumulation in soil, sediments, water and the food chain [9,10].…”

Survival and Growth of Bacteria in Treated Wastewater and Water Distribution Systems and their Implication in Human Health: A review

“…In many cases, these heavy metals are found in the treated sewage effluent and sludge at concentrations exceeding maximum permissible levels [14][15][16]. It is noteworthy that bacterial isolates from waste streams contaminated with heavy metals have also been found to be resistant to antibiotics.…”

“…Recycled treated wastewater is either returned to surface waters or reused and this has the benefit of reducing water demand, specifically in arid regions [12,16,24,[29][30]. Coliform bacteria including E. coli are used as indicators of pathogenic bacteria of enteric origin in treated water used for irrigation.…”