Industrial chemicals and microbial pathogens can contaminate any food. In recent years, the news media have broadcast many stories of illness and death related to bacteria-contaminated poultry, mercury in fish, aflatoxin in moldy peanuts, and viruses in uncooked shellfish. The Food and Drug Administration reports that food-borne infections caused by Salmonella alone are responsible for an estimated 6.5 million cases of human illness and 9,000 deaths annually in the United States. 312
The primary safety concern with wild-grown algae comes from contaminant algal species that, under certain conditions, may grow in the same lake and thus be harvested along with the food algae. Known toxins that could potentially contaminate edible algae are amenable to regulatory assessment, using reliable laboratory analysis for signs of toxins, along with safety guidelines and consumption rates for the food. 313,314 A reputable microalgae company will guarantee that accurate and independent tests are done on each batch of harvested algae to ensure purity and safety.
Freshness is Important
Another concern is how fresh or nutritionally intact the final product is. One of the best freshness indicators for microalgae is the amount and kind of chlorophyll breakdown products it contains. In one comparison of five companies that harvested wild microalgae the percentage of intact chlorophyll ranged from 0 to 65% (average of 21%). 315 Breakdown products of chlorophyll include pheophytins and, potentially, pheophorbides. 3 The latter are known to be toxic. Careful harvesting and avoidance of heat will minimize these breakdown products. The same is true of any species of microalgae and also of all chlorophyll-rich "green" foods.