
Morel mushroom hunting filled much of last week. The main reason for May camping in northern Michigan is morels. Trekking through the deep woods brought new appreciation for chemistry this year.聽
Dangers, at least in past years, were scarce in the morel woods. It is rare to see animals, with the occasional porcupine being the most dangerous looking, yet representing little real danger. I am now in my 32nd year walking in the Michigan woods. This is the first time I鈥檝e found a tick.聽
There are over of ticks worldwide.聽Only about , but they are .聽Some have linked the increasing .聽Cold keeps arthropod pests at bay, but the coldest .聽Pests now survive the milder winters. Some link the and other to increasing range.聽Whatever the cause, we now have at least five problematic ticks in the Michigan woods.聽
The present in the U.S. Mercifully, all aren鈥檛 . .聽 All are scary. A tick bite can also cause a potentially fatal .聽 An encounter with a tick can be a life-changing event.
Ticks are an unwelcome addition to the menagerie of bloodsucking beasts found in the wilds of Michigan. There are pesky mosquitos, annoying black flies, and blood-sucking leeches. I hate them all. Amber-encased ticks tell us they鈥檝e been around , just as Jurassic Park taught us about .聽 The prevalence of both, success over eons, and expansion indicate it must be a ripe ecological niche. It is unlikely they are going away. We will have to adapt.聽
The adaptations available are decidedly chemical. Chemophobic friends willingly spray themselves, spray their yards, ignite chemical-containing incense and, more recently, wear little chemical-spewing fans all in hopes of keeping the bloodsuckers away.聽
鈥淭hey don鈥檛 bite, they don鈥檛 even light鈥� was a memorable line in a TV commercial for insect repellents. That commercial heralded the power of DEET, N,N-diethyl-meta-toluamide or N,N-Diethyl-3-methylbenzamide. It is the most widely used insect repellent, one I鈥檝e used for years. I鈥檝e used Picaridin , or .聽DEET feels greasy. Picaridin is non-greasy and odorless. Both are proven to work on both mosquitos and ticks when applied to skin and clothing. DEET can cause acute health effects, though it has never happened to me. Seizures, uncoordinated movements, agitation, aggressive behavior, low blood pressure, and skin irritation have all been .聽Picaridin has fewer . Sadly, aren鈥檛 kind to the natural oils. Studies and my experience indicate the synthetics work better.聽
Pyrethroids loom large in arthropod abeyance. are compounds with structures similar to compounds extracted from chrysanthemum flowers, . They are rapidly absorbed and paralyze insect nervous systems. The DoD for bug avoidance relies on application of DEET or Picaridin to skin and treating clothing and bed nets with , (3-phenoxyphenyl)methyl 3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane-1-carboxylate, a synthetic pyrethroid.聽 Pyrethroids aren't absorbed through human skin very well, but are not intended for direct skin application. They do enter the body if eaten or inhaled. Pyrethroids are generally considered safe for humans, but .聽When used with DEET or Picaridin, Permethrin, on clothing is an effective contact poison for a broad range of biting arthropods. Ticks and mosquitos are no match.聽
Spatial repellents are things that keep bugs away. Candles, incense and devices emit repellents to form a bug free zone making the campsite livable. They make a cloud of pyrethroid vapor that serves to disorient or kill flying bloodsuckers. , [2,3,5,6-tetrafluoro-4-(methoxymethyl)phenyl]methyl 2,2-dimethyl-3-(1-propenyl)cyclopropanecarboxylate, or other pyrethroids are used in several of the most effective spatial repellants.聽
Volatilizing pyrethroids means breathing them. They are rapidly absorbed through the lungs. Measuring the metabolite 3-phenoxybenzoic acid shows .聽I am concerned, but, for now, willing to trade breathing the vapors for fewer bites.
Some say the pyrethroids are safe, deemed or because their foundational structure comes from a flower. That perturbs me. Pyrethroids are ubiquitous, having replaced several classes of insecticides deemed more problematic. They kill all insects, including bees. They are highly toxic to fish and other animals living in salt water or fresh water. We are only and toll of that widespread use.聽Metofluthrin has a tetrafluorinated aromatic ring. Permethrin is dichlorinated. These compounds are far from natural.聽 as a 鈥渓ikely to be carcinogenic to humans.鈥澛燛xposure was recently linked to .聽If safe means incapable of causing harm, these compounds are far from safe, but they may be safer than going without聽聽
My safety in the woods now depends on chemicals. I will move to spraying my clothes with Permethrin to ward off ticks, in addition to using DEET or Picaridin on my skin. I will trade chemical exposure for reduced risk of arthropod-borne disease, or at least for a reprieve from bloodsuckers. As arthropod-spread diseases spike, I am trading risks.聽

Mark Jones is a frequent speaker at a variety of industry events on industry related topics. He is a long-time supporter of ACS Industry Member Programs providing both written and webinar content, supporting the CTO Summits, and as a former member of Corporation Associates. He currently serves on the ACS Committee on Public Relations and Communications and the Chemical Heritage Landmark Committee. He is a member and former chair of the Chemical Sciences Roundtable, a standing roundtable of the National Academies of Sciences, Engineering, and Medicine. Mark is the author of over a dozen U.S. patents and numerous publications.
The opinions expressed in this article are the author's own and do not necessarily reflect the view of their employer or the American Chemical 中国365bet中文官网.