The pharma industry in Hyderabad is polluting the environment with antimicrobials which in turn may contribute to a rise in drug-resistant infections, a new study published in the journal Infection alleges. Claiming that Indian authorities have not done enough to ensure efficient treatment of waste water discharged by the pharma industry, the study also calls upon European regulators to ensure enforcement of regulations during the manufacturing process.
Water samples tested
Hyderabad is a global market for bulk drug purchasing with 50% of India’s drug exports, pegged at over $3 billion, coming from the city. Researchers from Leipzig University Hospital, Germany, tested 28 water samples from difference places in the city, including sewage from around pharma manufacturing units in Patancheru-Bollaram Industrial Development Area on the outskirts. They found “unprecedented antimicrobial drug contamination” in the samples collected from around the pharma units.
“Bacteria develop resistance when they are over-treated with antibiotics but effluents with drug residue from hospitals and pharma units can also contribute. Excessive use of antibiotics either with or without prescription should be avoided even as it is essential to have efficient effluent treating systems with stringent legal norms,” said Pratyoosh Shukla, general secretary, Association of Microbiologists of India.
The crisis of drug resistance is exemplified by the spread of drug-resistant tuberculosis in India and growing concerns of the World Health Organization (WHO) that the disease could affect the international community, as tourists from India may return with deadly superbugs. Another stark manifestation of drug resistance in India is the sheer number of neonatal deaths attributed to it, an estimated 58,000 every year, followed by hospital-acquired infections that fail to respond to last-resort treatment.
The Infection study found that 23 samples contained multidrug-resistant bacteria. Resistance was seen to a broad range of antibiotics including a family of powerful drugs known as carbapenems, broad-spectrum antibiotics that target several species of bacteria and were originally synthesised to specifically treat drug-resistant infections. Bacteria-producing enzymes to break down carbapenems were found in all 23 environmental samples.
More significantly, the study claims that all samples contained antimicrobials in concentrations far exceeding maximum permissible environmental concentrations of these drugs. Though no universally accepted standards exist on just how much of a specific drug in the environment is too much, the study relies on limits which in turn are based on minimum concentrations required to kill bacteria. For long now low-level exposure to antimicrobial drugs in the environment has been feared for inducing resistance.
In one sample, the antibiotic moxifloxacin, used for many conditions including respiratory and skin infections, was found in maximum concentration of 694.1 microgram per litre, over 5,000 times the environmental limit of 0.125 microgram per litre. These environmental limits were proposed in a past study.
An even bigger concentration of the anti-fungal drug fluconazole (2,36,950 microgram per litre) was found in one of the samples, way above the proposed environmental limit of 0.25 microgram per litre. Residues exceeding limits were also found in the Musi river, which carries treated sewage away from the city. Treated wastes from pharma companies, along with rest of the sewage from the city, are eventually let into the river.
Industry reaction
Reacting to the study, drug manufacturers in Hyderabad maintain that it does not sufficiently link antibiotic resistance to pharma effluents and that they comply with Pollution Control Board norms. “Drug resistance is a problem and we have said that we will not allow any company to pollute the environment. We have norms and have also said that we are ready to cooperate on any issue. These studies are done without transparency by not involving Indian regulators,” said R. Uday Bhaskar, Director General of Pharmexcil [Pharmaceuticals Export Promotion Council], the government’s agency for promotion of pharma exports.
To counter claims made by European researchers, University of Hyderabad (UoH) scientists have carried out a study commissioned by the Bulk Drug Manufacturers Association (India) that shows multidrug-resistant bacteria can also be found in areas where no pharma units exist. As it looked only for bacteria, the UoH study, however, could not respond to specific allegations made by the Infection study — the findings of drug residues in high concentrations around specific pharma units. Industry representatives say they will commission another study before responding to this accusation.
For Patancheru locals and environmental activists, the Infection claim only buttresses the perception that the government is not doing enough to curb untreated discharge. “Our groundwater continues to be contaminated and agriculture stands affected. While industrial units can claim there is no chemical discharge, the waterbodies continue to receive inflows clearly loaded with chemicals,” said K. Chidamberum, who has legally fought the pharma industry and the government under the aegis of Citizens for Better Patancheru Constituency.
Prof. Shukla expressed the need for having environmental standards for antimicrobial drugs specific to the country and emphasised vigil as well as awareness about release of drug-laden effluents.
rohit.ps@thehindu.co.in
