UN world water report: cities breeding mosquitoes and the poor paying too high a price

Population growth, global warming and agricultural expansion are placing unprecedented burdens on the planets water resources, says a UN report.

Inertia from world leaders will only worsen the impending global water crisis, with the world likely to miss targets of halving the proportion of people without access to safe drinking water by 2015, says the UNs World Water Development Report. By 2050, two billion people could be facing water scarcity, with drought-prone regions likely to experience more erratic rainfall from warmer weather, and agriculture continuing to swallow 70% of the worlds water.

According to the report, water supplies dropped by a third between 1970 and 1990, while water consumption has almost doubled in the last 50 years. A child born in the developed world consumes 30 to 50 times the water resources of one in the developing world. And without better wastewater management, the 12,000 cubic kilometres of freshwater currently polluted across the world looks set to rise to 18,000 cubic kilometres by 2050 equivalent to nine times the annual consumption by irrigation. Industry may also have to curb its habits, with current consumption of 22% of the worlds water predicted to rise to 24% by 2025, equivalent to 1,100 cubic kilometres a year.

Sanitation is also struggling, with cultural factors further complicating the logistical and financial difficulties in providing adequate sanitation for the worlds poorest, says the report. Water prices can be punitively high in areas with scarce resources. Water vendors in Delhi charge US$4.89 per cubic metre, while families with piped connections pay just US$0.01, according to a survey published in the report.

In terms of staving off world hunger, the UNs Millennium Goal to halve the proportion of people suffering from hunger by 2015 may not be achieved before 2030. A predicted surge in irrigated crops could see another 45 million hectares demanding 14% more irrigation water, although scientists efforts to improve the efficiency of irrigation, which typically wastes 60% of water, are already showing promise.

Equally positive is the halving in the amount of arable land is now required to grow the same amount of grain as in the 1960s, with yields predicted to continue rising. And despite doomsday predictions of looming water wars, the report finds evidence to the contrary, with the majority of countries peacefully co-operating over resources and 200 water-sharing treaties signed.

More worrying is the lack of awareness amongst decision-makers that they share aquifers with other countries, with less attention paid to groundwater than river water. Cities have becoming breeding grounds for rats and mosquitoes, with Asian rooftop water storage tanks and US stormwater retention ponds attracting mosquitoes along with malaria and the West Nile virus. Water remains the largest natural disaster killer, with 90% of those succumbing to natural disasters killed in floods and droughts.

While New Zealand, Canada, Congo and Iceland have between 80,000 and 600,000 cubic metres of water per person, Kuwait, the Gaza Strip and the United Arab Emirates have less than 60 cubic metres per person. Belgium joins India and Morocco as the countries with the worst quality of groundwater from industrial and sewage pollution, while Finland, Canada and the UK enjoy the best quality water.

This week in Canada, the electronics and information technology industries have formed Electronics Product Stewardship Canada (EPS Canada), a not-for-profit organisation intended to promote solutions for sustainable management of electronic waste. 

Organic food reduces pesticide residues in children

A study of two to five-year olds in the US has found that consumption of organic food can have a significant effect on childrens pesticide exposure.

The study, by scientists at the University of Washington, investigated 43 children from the Seattle area who either ate mostly organic or mostly conventional fresh fruit and vegetables and fruit juices.

The children eating primarily organic diets had significantly lower organophosphorus pesticide metabolite concentrations that those eating conventional diets. One group of metabolites, the dimethyl metabolites, were found to be around six times higher in children eating conventional diets.

The scientists have drawn the conclusion that consumption of organic produce represents a relatively simple means for parents to reduce their childrens exposure to pesticides.

Children eat more food per body mass than adults, and their diets are often higher in rich in the sort of foods that are likely to contain higher levels of pesticide residues, such as juices, fresh fruits and fresh vegetables, the researchers explained.

Organic foods have been growing in popularity over the last several years, said Dr Jim Burhart, Science Editor for EHP. These scientists studied one potential area of difference from the use of organic foods, and the findings are compelling.

Other possible sources of pesticides were investigated, such as from drinking water or home use of pesticides. However, these were found not to have an impact on the studys results.

The researchers admit that there were some limitations to their study, including concern that the children were not necessarily representative of children in the area as a whole. A second problem is that 100% of a dose of pesticides is not excreted in urine, so that it is likely that doses are underestimated.

There have been other studies that back up the researchers claims. A study published in 2001 found that of 110 urban and suburban children, all but one of the children had measurable levels of organophosphorus pesticide metabolites in their urine. The one exception was a child whose parents reported buying exclusively organic produce.

A similar study, published on 26 February in the Journal of Agricultural and Food Chemistry has revealed that organically grown foods are higher in cancer-fighting chemicals that conventionally grown foods. The research suggests that pesticides actually thwart the production of phenolics, a type of antioxidant, which plants produce to protect themselves against pests.

The researchers studied a type of blackberry, and found that those grown organically had around 50% more antioxidants than those grown conventionally.

I found that the higher level of antioxidants is enough to have a significant impact on health and nutrition, and its definitely changed that way I think about my food, said Alyson Mitchell of the University of California, and lead author of the paper.

Bicycle pumps and playgrounds solving energy problems

Energy production is childs play, particularly if you have a bicycle pump, a tyre, and a group of energetic children letting off steam on playground equipment such as seesaws, swings and roundabouts. This isnt a riddle, says a scientist from the University of Michigan, but a cheap and simple way to generate electricity in developing countries.

Whilst children play on the playground equipment, such as a seesaw, air is compressed by bicycle pumps, stored in tanks, and later used to charge batteries. The energy can then be used to power devices such as lights, sewing machines and fans.

A child spending three minutes during its school break time on a teeter-totter provides enough energy to power a 20W lamp for one to two minutes, the systems inventor, Dr Raj Pandian stated. This can be invaluable in the dry season in developing countries, when there is less electricity being generated.

The reason why I have chosen pneumatics is that its a simple and safe system, said Dr Pandian. He has developed a small prototype in the laboratory, and is planning to use the device on a few local playgrounds in Michigan in the summer.