“We found that thiamine deficiency is much more widespread and severe than previously thought,” Balk says. Given its scope, he suggests that a pervasive thiamine deficiency could be at least partly responsible for global wildlife population declines. Over a 60-year period up to 2010, for example, worldwide seabird populations declined by approximately 70%, and globally, species are being lost 1,000 times faster than the natural rate of extinction (9, 10). “He has seen a thiamine deficiency in several differ phyla now,” says Fitzsimons of Balk. “One wonders what is going on. It’s a larger issue than we first suspected.”
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Balk fears that a single pervasive factor, such as an atmospheric pollutant, may be depleting the environment of thiamine at its sources, including phytoplankton and bacteria, affecting the entire food chain. To see how far the problem reaches, he is now looking at upstream terrestrial wildlife such as elk (Alces alces). Balk is also investigating whether any of several pollutants might interfere with the oxidation, hydrolysis, or synthesis of thiamine.
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Sañudo-Wilhelmy has measured very low levels of B vitamins, including thiamine, in coastal waters around California. Other researchers have estimated similar scarcities in some areas of the open ocean (16). Warming waters due to climate change could explain the seawater vitamin scarcity, he says. Warmer temperatures speed bacterial growth, making the microbes consume more B vitamins than they produce—gobbling up the vitamins before the phytoplankton can take their share.
All are couched with the fact that more research is necessary into the cause or causes.