In Tacoma we have roads. Road create mobile source emissions. Then we have stationary source emissions. Stationary sources create emissions. Like wood fired boilers, home wood burning fireplaces, gas heating systems, gas powered generator sets, and natural gas burning stuff that strikes metal surfaces—all stationary sources that just don’t move around. Now comes the methane, LNG, and Methanol process with burning flare(s) to Tacoma; therefore, the average person might just put those flame flare(s) combustion byproducts into the stationary source combustion emission byproducts category added to the Tacoma Community airborne environment inventory. But what does that mean for Tacoma Community people health and wellness? The past study results can shed some informative lite on this dark, nobody wants to address subject of human health and source emissions.
There exists a number of articles that discuss these sources study present results. See generally, Formaldehyde and Cancer Risk National Cancer Institute, http://www.cancer.gov/about-cancer/causes-prevention/risk/substances/formaldehyde/formaldehyde-fact-sheet (last visited Feb 11, 2016); see also, Inhalation of Aldehydes and Effects on Breathing US EPA, http://cfpub.epa.gov/ncer_abstracts/index.cfm/fuseaction/display.abstractDetail/abstract/2313/report/0 (last visited Feb 11, 2016)
Also, we have just the simple breathing of vapors, like methanol, that have some human health questionable impacts long term? See, Does Inhalation of Methanol Vapor Affect Human Neurobehavior? US EPA, http://cfpub.epa.gov/ncer_abstracts/index.cfm/fuseaction/display.abstractDetail/abstract/2305/report/0 (last visited Feb 11, 2016)
Enjoy your reading and making your own inference as to who and how things are burned or just inhaling the vapors that are not good for human health long term exposure. You be the judge, for your own health sake.