Caspian Sea: State of the Environment 2019

tional rules. All production waste (drilling mud, drill cuttings, etc.) from drilling sites is transport- ed to shore by service companies for further pro- cessing at specially constructed facilities. To improve state monitoring of seawater quality, CaspEcoControl purchased new, modern instru- ments for determining dissolved oxygen content in seawater, pH levels, and concentrations of oil products, ammonium nitrate, nitrites, phenols Agriculture is one of the most important sources of pollution worldwide, and this is also the case in the Caspian littoral states. Problems associated with harmful pesticides, fertilizer use and poorly treated livestock waste are widespread, and the latter two may have contributed to eutrophica- tion in the Caspian Sea as early as 2005 and 2006. Water quality is especially vulnerable to agricul- and other pollutants. 4.3. Agriculture

tural waste discharged into rivers running into the Caspian Sea (GRID-Arendal 2011). Environmentally harmful pesticides are gener- ally cheap and readily available to both small- scale enterprises and large-scale farms, which use them to ensure high yields from their ag- ricultural land. Chlorinated pesticides such as dichloro-diphenyl-trichloroethane (DDT) and hexachlorocyclohexane (HCH) have been used along the Caspian coast (GRID-Arendal 2011). Another widespread and well-known problem related to agriculture is increased nitrate load- ing as agricultural production intensifies. Nitrate loading in the Tajan watershed in Iran originates primarily from agricultural land where nitrates are widely used in paddy fields and orchards (Ra- jaei et al. 2017). In addition, the use of organo- phosphate pesticides in agricultural practices in the Southern Caspian basin also poses a threat to humans and wildlife (Nasrabadi et al. 2011)

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