admintoxins which are threatening both human health and the environment. Over time mercury has been concentrating in the soil, water and living organisms.
Although it’s potentially toxic in highly contaminated areas, research has shown that mercury can be a threat to the health of people and wildlife in many environments that are not obviously polluted.
Main sources of mercury contamination
Metal processing; Coal incineration; Incineration of municipal and medical waste; Gold mining; Discharge from hydroelectric, mining and paper industries; Cement production and Accidental spillages.
Effects of mercury:
Mercury in the air may settle in water bodies and affect water quality. Mercury accumulates in fish at levels that may harm the fish and the other animals that eat them.
Mercury exposure on wildlife can include mortality (death), reduced fertility, slower growth and development and abnormal behaviour that affects survival.
Research indicates that the endocrine system of fish, which plays an important role in fish development and reproduction, may be altered by the levels of mercury found in the environment. Once present in aquatic ecosystems, elemental and inorganic mercury can undergo chemical transformations to methylated mercury species and enter the food web and high level predators such as birds, sea mammals and humans could be in danger of contamination.
On human beings
Continued inhalation exposure to elemental mercury causes tremors, gingivitis and excitability. At very high levels, inhalation of elemental mercury can cause death. For foetuses, infants, and children, the primary health effect of mercury is impaired neurological development. Mercury exposure in the womb, which can result from a mother’s consumption of fish and shellfish that contain mercury, can adversely affect a baby’s growing brain and nervous system. Impacts on cognitive thinking, memory, attention, language, and fine motor and visual spatial skills have been seen in children exposed to mercury in the womb.
Impairment of the peripheral vision; disturbances in sensations (“pins and needles” feelings, usually in the hands, feet, and around the mouth); lack of co-ordination of movements; impairment of speech, hearing, walking; and muscle weakness. People concerned about their exposure to mercury should consult their physician.
Mercury primarily causes health effects when it is breathed as a vapour where it can be absorbed through the lungs.
On animals
Exposure of animals to mercury affects the immune system, alters genetic and enzyme systems, and damages the nervous system. Common sources of high levels of mercury contamination.
What is Zimbabwe doing about it?
In response to this ever increasing problem a committee, the Intergovernmental Negotiating Committee on Mercury was set up to develop a legally binding instrument on mercury. Zimbabwe is a member of this committee.
The instrument proposes a progressive and systematic phasing out of the use of mercury and mercury based products overtime. The document will be binding on all member states that accede to the document and they will be obliged to adhere to its provisions.
The document puts an obligation on member states to ensure there is informed consent from the receiving state in relation to the trade in mercury or mercury based products. Trade in mercury or mercury-based products will be restricted to allowed purposes under the instrument and also domestic law, and only in quantities needed for those purposes.
The instrument will also put restrictive measures on the use of mercury especially in the mining sector.
There is a need for development of sustainable technologies to extract gold in preparation for the restrictions that will be imposed on trade in mercury.
The draft text for a Global Legally Binding Instrument on mercury is a document that seeks to address the globally recognised health and environmental problems associated with the use of mercury in mining, industrial and commercial activities.
The main benefit, legally, that the document brings to Zimbabwe is that it will be a reference point or provide direction on how national legislation can be developed to tackle the ongoing problem of controlling the use and influx of mercury into the country.
Currently, no legislation exists that effectively controls the use of this dangerous substance thus leaving loopholes which can be exploited at the expense of the health of the general population of Zimbabwe and also the preservation of our environment.
What does the law say about mercury?
Environmental Management Act Cap (20:27) as read with S.I 12 of 2007 states that, any person who imports, transports, stores or sells any hazardous substance must have a license for each purpose.
The 2013 World Environment Day commemoration will be held in the form of an environment expo, where there will be exhibitions and paper presentations on the following theme: Think, Eat, Save – Promoting Sustainable Consumption
Those willing to present papers should send an abstract of not more than 400 words to the following emails: [email protected], [email protected]. The submissions should be made before 17 MAY 2013
Please note: Exhibition space and presentation of papers is free of charge. For more information you can contact the following: V. Gundu, Y. Chingarande, T. Njovana, K. Mupandaguta on (04)701681-3.
The Ministry of Environment and Natural Resources Management invites individuals, companies, institutions and organisations who wish to participate in this event to register with the Ministry. Date: 5 June 2013, Time: 0830hrs – 1600hrs. Venue: Meikles Hotel, Harare. Exhibitions: Africa Unity Square.
Please talk to us. We are always ready to listen. Email: [email protected]; Tel: 04 305543; Tollfree 08080028.
Online Reporter