Brands of a religious water being sold to Muslim worshippers in Barnsley are not the genuine product, say trading standards officers.
Zam Zam water is usually drawn from a well in Mecca, Saudi Arabia, by pilgrims making their trip to the city.
Officers have had complaints from Muslim organisations about the so-called "Natural Zam Zam Water".
Saudi Arabia's embassy said the genuine water from the well cannot be exported or sold commercially anywhere.
Tests have shown the water being sold contains unacceptable levels of nitrate and one instance of arsenic content.
Trading standards officers say the so-called "Natural Zam Zam Water", which comes in 0.5 and 0.25 litre plastic bottles, contains nitrate levels beyond the limits for natural mineral water, spring water and bottled drinking water.