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LIMCOM's current ongoing interventions being undertaken include:
Groundwater is generally considered the cheapest and most sustainable source of clean water for rural areas of southern Africa (Holtzhausen 2005). However, high levels of nitrate are a concern in this area. Recent studies (Tredoux et al. 2001; Tredoux and Talma 2006) have shown that excessive levels (40 mg/L), or higher, can be dangerous to human health and can cause methamoglobinaemia, also known as blue baby syndrome, in infants. Blue baby syndrome occurs when nitrate is converted to nitrite in the baby and inhibits the distribution of oxygen in the baby's blood. If not identified and treated this condition can be fatal.
These serious effects are not restricted to humans. Nitrate poisoning of cattle has resulted in devastating losses across southern Africa. In 2000, 356 heads of cattle died on Ghanzi River in the Ghanzi-Karakubis area in Botswana. Nitrate levels have been detected above 500 mg/L in the southern Kalahari. Nitrate poisoning is not contagious, but because of the misconception that it is, farmers are often not able to sell their cattle when it is suspected.
The Document Library of the Limpopo RAK contains a report by Vogel et al (2004) on Nitrate Hotspots and Salinity levels in Groundwater in the Central District of Botswana; another part of the Limpopo River basin severely affected by nitrates.
Nitrate can be found naturally in the environment (see box below), but for the most part is a result of anthropogenic activities and pollution from point sources. Improperly treated wastewater infiltrating into the groundwater source is one of the main sources of nitrates. Once nitrates become abundant in a groundwater source their removal is usually impossible without the application of expensive technology.
From the southern Africa regional studies it can be concluded that:
Source: Tredoux and Talma 2006
A HEIFER IN BOTSWANA KILLED BY
NITRATE POISONING FROM
CONTAMINATED GROUNDWATER.
SOURCE: PROZESKY 2000
STOCK LOSSES FROM NITRATE POISONING HAVE BEEN SIGNIFICANT ACROSS THE WESTERN (BOTSWANA) AND SOUTHERN (SOUTH AFRICA) PORTIONS OF THE BASIN.
SOURCE: PROZESKY 2000
LIMCOM's current ongoing interventions being undertaken