Scientists have warned about the contamination of Chinese rice with mercury
Depending on future technologies and political solutions, the volume of mercury precipitation may increase by almost 90% or to fall by 60% by 2050.
The mercury contamination affects not only fish, but also rice, say experts at the Massachusetts Institute of technology (MIT). The work of the coal enterprises and other industries leads to the fact that the metal enters the atmosphere, it accumulates and precipitation falls into water and soil where it is absorbed by rice. About his work published in the journal of Advancing Earth and Space Science, scientists reported in the material for publication the Conversation.
The experts said that the fall in water mercury some microorganisms turn into methylbut — more toxic compound can accumulate in the body.
As the rice fields flooded throughout the growing period, the substance is formed there regularly.
Scientists have built a computer model to understand how the concentration of methylmercury in rice differ in the Chinese provinces. They found that the highest content of substances is observed in the Central Chinese provinces: Henan, Anhui, Jiangxi, Hunan, Guizhou, Chongqing and Hubei. There is formed a twice “mercury rain”. These regions produce 48% of rice in the country.
The researchers calculated that residents of the Chinese regions where the soil is contaminated with mercury, consume more acceptable, according to the Agency for environmental protection of the United States, standards of 0.1 mg methylmercury per kilogram of body weight. In large concentrations the compound can disrupt the body, including lower IQ. Though there are studies that indicate the negative effects and with lower amount of the substance in the body.
The study showed that the change of mercury emissions to the atmosphere can affect the concentration of the substance in rice. Scientists predict that depending on future technology and policies, the volume of mercury precipitation may increase by almost 90% or to fall by 60% by 2050, They suggested two scenarios. The first does not involve a new policy control of mercury emissions up to 2050 In the second China use less coal-fired power plants and introduced measures to control mercury emissions. The average concentrations of mercury in rice increased by 13% in the first case and decreased by 18% in the second.
Experts advocate an integrated approach that includes the fight against “mercury sediments”, polluted water and soil. They also propose to change the manufacturing process of Fig.
Experts recommend to alternate flooding with dryers to reduce water consumption, emissions of methane and concentration of methylmercury.
Experts draw attention to the fact that mercury pollution — a problem common throughout Asia, where growing use of coal, and rice is the staple food. To find out the distribution of emissions is important to all member countries of the Minamata Convention on mercury (interstate agreement aimed at protecting human health and the environment from anthropogenic emissions and releases of mercury and mercury compounds).