Over 200 commonly known diseases have roots in mercury toxicity. Various government entities will tell you of a number of products with mercury levels that are not harmful. The truth could not be farther from these statistics.
Consider that every item regulated with "safe" levels of mercury is rated individually and without regard for multiple exposures. Knowing that even the smallest amount of mercury is damaging, we can be sure that a daily exposure through medications, vaccines, antiques, auto parts, appliances, eye drops, cosmetics, water, foods, fish, dental fillings, fossil fuels, jewelry, electrical switches, skin creams, skin lightening creams, barometers, thermostats, fungicides, preservatives, light bulbs and so many of our daily use products is overwhelming.
With government standards at such permissive levels, knowing contaminants and how to limit your exposure is the only way to stay safe. Even the light bulbs you choose will matter far past your use as you consider they will be broken in landfills and the poison will leach into the earth to be returned as a contaminant again. There is no single use of poisons.