Some experts have found evidence that indicates that the U.S. could be using its labs overseas to conduct biological research that could threaten global public health, Xinhua News Agency reported on August 20.

The U.S. owns 336 biolabs in 30 countries around the world including in Europe, Central Asia, Africa and Southeast Asia, according to the data the U.S. submitted to the Biological Weapons Convention. The data also shows that the U.S. owns 26 biolabs with relevant infrastructure and a large number of pathogens in Ukraine, raising concerns amid the Russia-Ukraine conflict.

Igor Konashenkov, spokesman for the Russian Defense Ministry, claimed in a news briefing in March that Ukrainian biological projects were directly developed and approved by the Pentagon. One of these projects involved carrying out molecular analysis of particularly dangerous infections endemic to Ukraine and sample pathogens from old animal burial sites to obtain new strains of anthrax.

Russia also said the U.S. has invested $32 million for Ukrainian biolabs for a project called UP-8, where 4,000 servicemen were tested for hantavirus antibodies and 400 others for the presence of antibodies for the Congo-Crimean Fever virus.

Igor Nikulin, a microbiologist and a former member of the UN Commission on Biological and Chemical Weapons, said the U.S.'s investment in Ukrainian biolabs is not about medical science but rather serves military purposes "if the projects are fully financed by Pentagon."

Furthermore, there have been multiple reports related to the U.S.'s mishandling of dangerous viruses. In 2015, Pentagon said the U.S. military accidentally sent live anthrax samples to as many as nine labs across the country and to a U.S. military base in South Korea.

In 2016, local authorities in Okinawa, Japan announced that high levels of perfluorooctane sulfonate (PFOS), an ingredient used in fire-extinguishing agents, had been discovered in waterways near the U.S. Kadena Air Base. The waterway supplies drinking water to seven municipalities. The PFOS is categorized as an "emerging contaminant" which can be absorbed by oral ingestion, accumulating in the blood, kidney and liver. It cannot easily break down in the environment or the human body.

This raises doubts on the U.S.'s control over its biolabs overseas and calls for having an independent organization for supervision, preventing it from possible operation errors and leaks, Xinhua quoted some experts as saying.