Eighty percent of locally produced mixed fertilisers were found substandard or adulterated. This variety of fertiliser is most popular among the farmers as it contains nitrogen, phosphorus, potassium and sulphur.

Zinc sulphate were found substandard in 75 percent cases, SSP in 87 percent cases, sulphate of potash in 60 percent cases and gypsum in 43 percent cases, according to an analysis conducted by the Soil Research and Development Institute (SRDI).

SRDI, one of the six authorised laboratories in Bangladesh, has prepared an annual review of the fertilisers based on the tests conducted in 2005-06.

During the period, the laboratory collected 750 samples from the Department of Agricultural Extension (DAE), Bangladesh Agricultural Research Council (BARC), importers, fertiliser dealers, non-governmental organisations, private enterprises and law enforcement agencies.

SRDI found that in most cases, urea fertiliser is packed and sold as zinc sulphate. The figure for percentage of zinc in zinc sulphate should be between 22 and 36, but the samples tested revealed that the percentage of zinc is only 1 to 2 percent, SRDI officials said.

Unscrupulous businessmen are also making a huge profit by selling adulterated zinc sulphate. One kilogram of urea costs only Tk 7 while the price one kg of zinc sulphate is around Tk 20, they added.

Similarly, magnesium sulphate that costs only Tk 12 per kg is crushed and then sold as boron fertiliser, which sells at Tk 40 per kg.

Farmers are forced to buy adulterated and substandard fertilisers due to acute scarcity of fertiliser during the peak season, an agriculture ministry official said.

In 2004-05, SRDI examined 800 samples of various types of fertiliser collected from different markets across the country and found proof of adulteration in 56 percent of cases.

According to experts, adulteration of fertiliser is going on unabated because the persons involved are very influential and it is difficult to take action against them.

If the Fertiliser Control Act 2006 could be enforced properly, such practice of adulteration would have declined, they observed.

According to official statistics, there are 70 fertiliser factories in the county. but the experts suspect that there might have been more than 100 'fake' fertiliser factories across the country and most of them are located in southwestern districts of Jessore and Jhenaidah.

Mainul Ahsan, principal scientific officer at the SRDI, said the use of adulterated and substandard fertilisers leads to lower yield of crop and decline in fertility status and soil quality.