Speaking of DDT, I found this quote earlier this year, while writing a paper on gas chromatography for a chemistry class.

"The amount of time that a compound is retained in the GC column is known as the retention time. The technician should measure retention time from the sample injection until the compound elutes from the column. The retention time can aid in differentiating between some compounds. However, retention time is not a reliable factor to determine the identity of a compound. If two samples do not have equal retention times, those samples are not the same substance. However, identical retention times for two samples only indicate a possibility that the samples are the same substance. Potentially thousands of chemicals may have the same retention time, peak shape, and detector response. For example, under certain conditions, DDT has the same retention time as PCBs (polychlorinated biphenyls). Some believe that environmental testing showed erroneously high amounts of DDT. GC instruments showed only one peak for what is believed to be a mixture of DDT and PCBs. This experimental data led to the banning of DDT in the U.S. Bluntly, GC is '(O)ne of the quickest ways of getting the wrong answer in qualitative analysis'."

Link

How is bringing back Don't ask Don't Tell going to help with bed bugs?

DDT needs to be approved for certain situations.

Our concern for the environment is noble, but in this case, somewhat (not fully) misguided.

Please educate yourself. This links to a well-written and thoroughly researched article exploring the topic of DDT.

Link

JackieRabbit: Then the county's mosquito abatement program enlisted the help of a invertebrate zoologist at the local university. His solution: place Gambusia holbrooki, the eastern mosquitofish, in the sloughs. It worked like a charm.

Biological solutions like this never have unintended outcomes. (hint: see above comments about gorillas and velociraptors)

Kymry: DDT needs to be approved for certain situations.

No it doesn't. There are plenty of fine chemical products available which do not cause permanent harm. To suggest DDT is "special" is to suggest that Chemists found the bestest pesticide first, which is extraordinarily unlikely.

Seriously. How much denial to you need to be in to close your eyes to the fact that nest failure in the DDT was observably due to egg shell thinning, and that this problem went away with DDT? Or that the bird species whose populations declined were precisely those you would predict to decline if a pesticide was the source of problems? Or that the population declines were most severe in the bird species you would anticipate would have the most exposure to a persistent pesticide?

All the fish eaters died off, except those which locate food far out to sea. What is your magic explanation for that?

\Kymry: DDT needs to be approved for certain situations.

From your link: DDT remains legal for insecticide use in most areas where malaria is a major killer

came here for the jake robert pics. Leaving satisfied

JackieRabbit: I cannot believe that there are people here who are actually advocating the return of DDT. It is a horrible toxin and a powerful carcinogen. All I can guess is that those advocating weren't alive before the ban.

frank249: I recall a truck going through neighbourhoods spraying a fog of DDT to control mosquitoes with kids running behind it.

Yes, I remember this. And I know now that the kids who did this have much higher rates of cancer and having children with birth defects.

There are much better and eco-friendly ways of controlling mosquitos than pesticides. I used to work on a campus on the coast that had a lot of fresh water sloughs in the woods. The mosquito problem there was very bad. Arial spraying of pesticide didn't work. Then the county's mosquito abatement program enlisted the help of a invertebrate zoologist at the local university. His solution: place Gambusia holbrooki, the eastern mosquitofish, in the sloughs. It worked like a charm.

[citation needed]

It is amazing to me the number of people that still believe the hype about how bad DDT is. DDT is not a carcinogen:

Feeding primates more than 33,000 times the average daily human exposure to DDT (as estimated in 1969 and 1972) was "inconclusive with respect to a carcinogenic effect of DDT in nonhuman primates." [J Cancer Res Clin Oncol 1999;125(3-4):219-25]

A nested case-control study was conducted to examine the association between serum concentrations of DDE and PCBs and the development of breast cancer up to 20 years later. Cases (n = 346) and controls (n = 346) were selected from cohorts of women who donated blood in 1974, 1989, or both, and were matched on age, race, menopausal status, and month and year of blood donation. "Even after 20 years of follow-up, exposure to relatively high concentrations of DDE or PCBs showed no evidence of contributing to an increased risk of breast cancer."
[Cancer Epidemiol Biomarkers Prev 1999 Jun;8(6):525-32]

Someone already posted this link, but I'll post it again: DDT does not cause egg shell thinning:

Link

I think we should just breed an army of masked hunters to fight the bedbug invasion.

exvaxman: Not trolling, just repeating a statement I heard years ago -
Rachel Carlson through the ban of DDT is as big a mass murderer as Hitler due to the mosquitos that have killed children in Africa.

yeah - nut jobs are everywhere.

That statement is so indicative of mental retardation that it is not even wrong.

If you want to eradicate mosquitoes, you can't go wrong with good old Bacillus thurigensis, or BT:

Bathia_Mapes: It was legal in the U.S. until the ban in 1972. I suggest you look up "Silent Spring" and learn what DDT did to bird eggs, including those of the bald eagle. Use of DDT came close to making our national bird extinct.

When Rachael Carson did her studies mentioned in the book, she fed the birds a diet low in calcium.

The problem with DDT is simple:

Insects -- mosquitoes, for example -- are R-selectors. That is, they produce enormous numbers of offspring but put very little effort into each one. Think of oysters as the ultimate R-selector, with their millions of offspring, very few of which will ever become oysters. Basically, they spew gazillions of eggs everywhere, and hope for the best. Mosquitoes are far from the champions in the egg-production race, but a female mosquito can produce about 1,000 offspring in her two-week lifespan.

The reason that matters in the case of the mosquitoes is that DDT is, as pesticides go, moderately easy for insects to develop a resistance to. Let's say there is a .00001 chance -- that is, 1 in 100,000 -- for any given mosquito to have a genome that will allow it to survive DDT application and reproduce. So out of a million mosquitoes (not, despite what I sometimes think, the content of my back yard, but easily the content of a couple of acres in a mosquito-friendly area) you'll have 10 that are resistant to DDT. With all the competing mosquitoes killed off, they will be putting out those offspring like crazy. Two weeks later, your 10 mosquitoes will be 5,000 mosquitoes, and I'm sure you can see where this is going.

The other half of this problem is that the predators of mosquitoes are more likely to be K-selectors -- that is, creatures that produce fewer offspring but make a greater investment in each one. For example, lizards will lay only a few eggs a year, but their eggs are much larger, proportionately speaking, than mosquito eggs, and their offspring are more likely to survive as individuals than their R-selector equivalents. Also, their generation times tend to be much longer. Take mosquitofish, for example. They're common around here, and I use them for mosquito control in water gardens (Gambusia can live on what they catch in water so hot it kills water lilies). We tend to think of mosquitofish as R-selectors, but of course the whole thing is a spectrum, and they're a lot further K-ward than mosquitoes are. In the time it takes a female Gambusia to produce a dozen offspring, two generations of mosquitoes can grow, lay eggs, and die. In the time it takes those dozen new fish to grow to reproductive age, those mosquitoes have gone through another four generations. So six generations of mosquitoes for one generation of mosquito predators -- 12 fish, or billions of mosquitoes.

Now, the problem comes in when you kill off 99% of the fish and 99% of the mosquitoes. Let's say you kill off all but 10 individuals of each species. Your fish can produce a brood every month (to make the math easy) and produce 12 new fish (assumed to be 6 of each sex) each time, and those fish require 2 more months to grow to reproductive age, and then a month to actually gestate their first brood, etc. So in six months, you have your original 10 fish (they live for a year or two), and their first through sixth broods. That's 70 fish, of all sizes from big adults to tiny fry. Plus their first brood of 12 (half females) has produced its first, second, and third broods, for another 216 fish, their second has produced its first and second, 144 fish, and their third has produced its first, 72 fish. So at this point, when the grandfish of the original 10 individuals are just reaching breeding age, you have a total of 1,132 mosquitofish. Meanwhile, what have our 10 mosquitoes done in 6 months? Well, that's 12 generations for a mosquito. 1,000 offspring (half female) per generation. So in two weeks, our 10 mosquitoes are 5,000 mosquitoes. In four weeks, they're 2.5 million mosquitoes ... well, you get the point. Their replacement time is much, much shorter than even a very prolific predator.

So in the end, you've got mosquitoes that are highly resistant to DDT (which was observed, by the way, within a few years of first use in any given area) and you've killed off all the other things that might eat them. Not only is your original problem back, but it's had puppies. The mosquitoes laugh at your sprays and their predators are dead.

That's the real problem. Not whether we want bald eagles or not, not whether the American Council on Science and Health is a partisan group or not, not whether any given person, group, or idea is divine or satanic ... simply, DDT doesn't solve the problem. It makes it look like it's solved for a few years, but then it's back and worse than ever ... usually after the people doing the spraying have declared the mosquito/malaria/yellow fever/whatever problem solved, accepted their awards, and moved on.

DDT has some uses. But despite what the people who want to make a political issue out of it instead of a scientific one thing, it's not miraculously better than more modern pesticides. It's not actually even all that good. It looked good when it was first introduced because it was the first really effective pesticide and it was being used on totally naive populations. Think of it, in a sense, as an analog to penicillin: amazing stuff when it first came out, but misused in numerous ways, and now virtually ineffective. Against a modern population of mosquitoes, it's about as useful as penicillin is against MRSA or multi-drug-resistant TB.

PaLarkin: Bathia_Mapes: It was legal in the U.S. until the ban in 1972. I suggest you look up "Silent Spring" and learn what DDT did to bird eggs, including those of the bald eagle. Use of DDT came close to making our national bird extinct.

When Rachael Carson did her studies mentioned in the book, she fed the birds a diet low in calcium.

Did she feed every fish-eating bird on the Continent low calcium? Do you have an explanation for why the shells of ALL fish-eating birds became fragile, then magically became slowly better after the DDT ban?

My parents were avid birdwatchers. I remember a trip to Florida as a child and them hoping they might see an osprey. I was in Florida a few weeks ago, and ospreys were everywhere. I got a great picture of a young osprey testing out his wings on the edge of a nest. Now, as to what has changed ... reversal of habitat loss? humans catching fewer fish? something else? ... I don't know. But there sure are more ospreys.

Hmmm.... My cat is now toxic to fleas. After we tried less drastic measures, Advantage was the thing that finally knocked down the flea infestation. I like the avermectin idea. I haven't had a bedbug problem (knocking on wood) but if I do, becoming toxic to bedbugs would be sweet revenge.

OnlyM3: Bathia_Mapes

It was legal in the U.S. until the ban in 1972. I suggest you look up "Silent Spring" and learn what DDT did to bird eggs, including those of the bald eagle. Use of DDT came close to making our national bird extinct.
I suggest you look up how that book is a complete fraud based on ZERO facts. The author is a complete fraud, right up there with Spoon benders and Dowzers.
Wrongful ban on DDT costs lives
[www.upl.co image 640x188]


But hey DDT ban kills brown people so of course you are all for it.
[3.bp.blogspot.com image 250x400]

DDT kills one in every thousand people. Malaria kills a lot more than that. But I'm sure you never thought that through.

Carth: Are there a lot of bald eagles in NYC and other major urban areas?

More than you'd think. We actually have a couple of nesting pairs inside the Philadelphia city limits. It's not something that gets a lot of coverage because the people who actually know where the nest sites are keep that info secret to keep the birds from being disturbed.

We also have so many hawks now that I've seen them sitting on the edges of roofs in my neighborhood and found pigeon carcases in my back yard.

Worldwalker:
So in the end, you've got mosquitoes that are highly resistant to DDT (which was observed, by the way, within a few years of first use in any given area) and you've killed off all the other things that might eat them. Not only is your original problem back, but it's had puppies. The mosquitoes laugh at your sprays and their predators are dead.

This, THIS, THIS!! This can not be repeated enough, given all the righties under the dangerous and ignorant delusion that nature exists to serve mankind. If you push nature, nature pushes back, usually with nasty, unintended consequences.

/regret that I can click the "smart" button but once for this
//and for brantgoose