Toxic Tuesday 3 – Revenge of the Hybrid Grass

By now, the story of the GMO grass that gassed a herd of cows in Texas has gone round the world at least twice, perhaps more.

Truth is still trying to catch up, and Deborah Blum has a good dose of truth available at Wired.

First, and pointed out by Blum, Tifton-85 is not genetically modified. It is a hybrid grass. Two different grasses were bred to produce this tasty green grass that is easy to digest. And even if it was GM, drought stressed grasses tend to produce cyanide. Non hybrid, hybrid, GMO, all of them are capable of doing this, and by so doing, can become toxic to grazers. The fact that many people are afraid of GMOs led people to immediately assume that the cows were killed by careless mad scientists at the behest of multinational corporations. Meh.

Second, I am highly skeptical that the plants were producing much cyanide gas. The cattle that were grazing in the field were most likely poisoned by eating the grass, not from breathing in cyanide, which would have caused a much higher dose to the cattle. The farmer, not eating the grass, but breathing the same air, would not have been affected.

Toxic Tuesday – Arsenic and old peppermints

Imagine popping a nice sweet into your mouth. It should be a pretty safe treat, right?

Not in Bradford, England, back in October of 1858.

Due to a mistake made by an assistant at a chemist’s shop, arsenic trioxide was sold instead of a filler called “daft.” The resulting batch of candies contained twice the lethal dose of arsenic in each candy.

Within days 25 people died, while at least 90 adults and 50 children became extremely ill. Counted among the stricken was Humbug Willie himself, who became sick from handling his own candies.

The aftermath of this accidental mass poisoning led to a requirement that arsenic include a coloring agent so that it would not be mistaken for other chemicals, as well as tighter regulation of arsenicals (chemicals containing arsenic). In the US, problematic patent medicines and disease outbreaks from food led to the passage of the Pure Food and Drug Act, which created the Food and Drug Administration.

This case reminds me of one of the truisms of toxicology, that laws regulating poisons are written in blood. (Laws regulating poisson are written in fish-hooks)

Science Tidbits June 19, 2012

Fast one today, as I spent a fair bit of time today at the Lexington Humane Society making friends with the cats and dogs. It’s June, which means that there are lots of adorable little kittens out there in need of homes, but don’t overlook the wonderful adult animals out there. We have three cats from LHS, two of which were adopted as adults. It is easier to place kittens into loving homes than adult cats who lack the tiny furball cuteness of the larval cat. With an adult cat, though, you have the knowledge of what the cat’s personality is and you know that you have brought home a special friend that may have spent several months in a small cage. If you can’t give a cat a good home right now, consider making a donation of food or money (call first and find out what they need).

On with the show.

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Top story, and for good reason, a Chicago woman has been cured of Sickle Cell Anemia! This isn’t a first ever, but is wonderful to see! Her bone marrow was killed via radiation and bone marrow carrying the gene for normal hemoglobin was transplanted. This is a pretty major intervention, as you can imagine, but it is great to see that some people are getting relief from this painful disease.

Most courses on genetics use Sickle Cell as an example of a disease where people carrying one copy of the gene are protected against malaria, but people with two copies have a lethal disease unless the disease is treated. Even then, most patients have a much shorter lifespan and have to deal with a painful disorder and side effects from the treatment. This gives us hope that better treatments could be within reach… but will require a much improved donor database.

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Its National Pollinator Week, and Bug Girl has information on the importance of our pollinators. For a person who has kept honeybees, this is a week I can dance for. Insect collecting and photographing can be great projects for students from elementary school all the way up to undergraduate, with identification exercises, learning about habitat and ecological niches as needed. If some students are particularly interested, 4-H programs offer a chance for students to direct their own learning and to practice their public speaking skills.

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Class discussion topic for all ages and a chance to discuss the history of the exploration of space: Is it time to return to the moon?

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Following up on yesterday’s tidbit about mating strategies, the Giant Cuttlefish shows its colors.

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A fast Toxic Tuesday, a returning feature of this blog, a quick list of several incredibly deadly proteins, running the gamut from ricin, produced by a bean, to botulinum, produced by a bacteria.

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Finally, news on the textbook controversy in South Korea. Creationist groups had pressured publishers to remove evolution from textbooks without input from scientists. Scientists will now get their say, and hopefully this misadventure will end with science back in science texts.

Teach on.

Toxic Tuesday! Lion fish.

The first aid for a lion fish sting is to keep it under hot water (less than scalding). If you experience a severe reaction (trouble breathing) then go to the ER immediately! So if that is what you needed to know, you don’t need to skim the whole post for it.

This is the first post in a series of three on lion fish.

Since I got such a great response from the Copperhead post, I decided I needed to get some pictures of poisonous critters that make for good teaching examples. And so, I pulled up some photos from the last time I went to the Newport Aquarium, just south of Cincinnati Ohio. It was much better than the Creation “Museum” that I blogged about last year, but I knew that going in. I try to go at least once a year, and my trusty camera always goes with me.

Lion fish are some of the most beautiful fish in the sea, and have a nasty reputation for being extremely poisonous. Extremely is an overstatement, as I think about sea snakes as being extremely poisonous. Lion fish will give you a nasty sting, very painful, but not as bad as many people think.

This critter is particularly important to me as a toxicologist, but is is very serious threat to the reefs of the Atlantic. As a (beginning) scuba diver, the thought of losing so many beautiful reef ecosystems would be a terrible thing.

lion fish 1

Pterois volitans is native to the South Pacific, as are all other lion fish, where it is kept in check by natural predators and parasites and is sought after as a food item. All lion fish make for very popular aquarium fish (pics of other species can be found there as well as care directions), and they were probably accidentally released into the Atlantic from an aquarium. lion fish 7

Lion fish were first found in Florida in 1985, and the population was entrenched by 2000 to the point that sightings have become commonplace. They are most common in the Bahamas and Caribbean, but have been sighted Belize and Venezuela and north to New York and the Bermudas. How could these become so spread out so quickly?

lion fish 1

The Gulf Stream runs north along the east coast of the US and larva stage fish and egg packets get picked up and borne along by it. It may come as a surprise, but young tropical fish are commonly sighted off the coast of New York in the warmer months. Lion fish that end up near Long Island won’t make it through the winter, but any of their little brothers and sisters that managed to get off the Gulf Stream by, say North Carolina, will be able to make it, even if mom and dad live in the Bahamas. Think about that for a minute. From the point of spawning north, a single reproductive event can spread baby lion fish all along the coast. By the way, if you don’t read any of the other links, read the previous one. Actually, here it is again. Go for the pictures of the juvenile lion fish, stay for the engrossing description of how one minor discovery by a graduate student can become incredibly important to current research.

lion fish 2Lion fish are voracious predators

That gorgeous coloration tells predators to back off and at the end of some of those fins is a nasty venom delivery system. The tissue on their dorsal, pelvic and anal spines can all be pushed back, causing their venom gland to release a lovely cocktail of toxins into the unlucky recipient of the sting.

Interestingly, the poisons are protein based, and are are broken down by heat, which is why running hot water over a sting or putting a hot towel over the sting site makes for good first aid. Its sort of like frying an egg.

Lionfish anatomy from Essential Image Source Foundation

Lionfish anatomy from Essential Image Source Foundation

You really have to see these guys swimming to get an idea of how beautiful they are. They are simply one of the most gorgeous fish in the sea, but they don’t belong in the Atlantic at the cost of the already fragile reef system.

Tuesday Toxics – Copperhead!

A couple weeks ago, our department had its yearly retreat, which we always have at one of Kentucky’s state parks. This time it was at Jenny Wiley State Park, which was nice, and the cabins were excellent. On the way home I stopped off at Natural Bridge State Park, thinking I would hike up to the top, which I remembered was a pretty easy walk. Yeah. I was probably about 10 then, and in much better shape and full of the boundless energy. I didn’t bring a water bottle, it was hot, and I parked about as far from the top as I possibly could.

Sheesh, I am out of shape. I wisely gave up before the steepest part and went back to look for something a family that I passed on the way up mentioned. A copperhead snake (Agkistrodon contortrix) was just a few feet off the trail, and I had to get a picture. Crikey! I wandered back down the trail and heard a couple talking about the snake. The woman decided to walk down the trail, while the husband tried to provoke a reaction from the snake by poking it with a stick. Are some people intentionally stupid? Of course, he couldn’t get one of the most stand-your-ground venomous snakes to nudge, so after about 30 seconds he wandered off.

If he had tried to reach down to try to grab the snake, I would have shouted at him to stop, but up to this point he wasn’t anywhere near getting bit. Take this as a hint, don’t harass snakes. Even non poisonous ones can give you a bite that easily becomes infected. But don’t be horribly frightened of them, either. Just back off if they offer a threat display and if you don’t know what you are doing, don’t try to pick them up. Most poisonous snakes rarely bite unless you try to pick them up or attack them. People have even stepped on and near cottonmouths and other pit vipers (family viperidae, subfamily crotalinae) with no response, and they will run (slither) away in preference to striking. One of the fascinating things about the pit vipers is that they can give a dry bite or only inject enough venom to let you know they mean business. They don’t want to waste their venom.

Copperhead camouflage is so effective that they will just sit still rather than flee (not that they know it, its is probably an evolved instinctive behavior), so the first threat display from the well hidden copperhead is to give a dry bite, making them unusual for pit vipers. These little guys would really rather just be left alone. If you are working in an area known to have copperheads, be careful when cutting fallen logs or clearing brush. Many experienced woodsmen rev their chainsaws for several minutes before they start cutting a fallen tree to give any copperheads a chance to slither away.

But hey, enough safety with critters, pictures!

Copperhead

Copperhead

Without the flash, this little guy just about disappears. I completely missed him the first time I walked past. Their hourglass scale pattern is perfect camouflage against a background of dry leaves.

Copperhead camoflage

Copperhead camoflage

This species is named for its copper colored head.

Copper head

Copper head

I have to say, this is one of my better nature photographs. I’ll probably have the original printed and put it up in my office. The detail is incredible, as seen from the image of the head, which is full size, and the scales, which are half size. I am considering putting a few of my nature photos up for purchase. Let me know what you think.

OK, now a bit of the biology of these guys.
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