River Chenab pollution level crosses limits, fish toxic now

Fish species from the Chenab River can be toxic for human health and are potentially unfit for consumption due to the high level of trace metals and arsenic found in them, experts said in a study.

These findings were made through a research study carried out by taking out 65 samples of different species of fish from various locations at the Chenab River. Studies on the level of toxic elements into freshwater fish from Pakistan suggest that the rapid industrial and agricultural growth in the recent past has posed major threats to water resources in the country.

Titled as “Human exposure to trace metals and arsenic via consumption of fish from river Chenab, Pakistan and associated health risks”, the research was published in the international journal of Chemosphere.

It was conducted by a group of eight scientists with Ambreen Alamdar, Syed Ali Musstjab and Nadia Hanif, from Institute of Urban Environment, Chinese Academy of Sciences, Xiamen china, Department of Bio Sciences, COMSATS Institute of Information and Technology, Islamabad, and Department of Environmental Sciences, International Islamic University, Islamabad, respectively, as its main authors,

About 65% of the sample fish had a higher Target Hazard Quotient (THQ) value for arsenic metal, while 5% had higher THQ values for cadmium, chromium, zinc and cobalt, indicating possible toxic effects for consuming population.

The THQ is known as a ratio of potential exposure to a substance, when value is greater than one, the product is considered to cause adverse health effects on humans. Overall, it was found that Cirrhinus reba, or Sooni, was the most toxic for human consumption within the examined fish population of the Chenab River.

According to the research, the herbivorous fishes such as the Cirrhinus reba and Catla catla, locally known as Sooni and Thaila, respectively, were found to be more readily accumulating trace elements such as arsenic, zinc, copper, and manganese through the water.

While in comparison, carnivorous species such Sperata sarwari (singhari), and Wallago attu commonly known as Mullee) were accumulating Chromium, Nickel and Lead via sediment and their diet through the bio-magnification process.

The research further revealed that when compared with international standards set by the Food and Agriculture Organisation (FAO) and the World Health Organisation (WHO) Expert Committee on Food Additives, the concentration of As (Arsenic) was found to be higher than the limits permissible for human consumption.

The Express Tribune