[tomjen3]

>E.g. you'd have to be crazily skeptical to suggest that the programs recommended by GiveWell aren't of positive expected value;

Their top charity for a long time was a mosquito net distribution agency. It turned out that the mosquito nets were used as fishing nets instead and, since they were treated with insecticide, polluted the local lakes.

[rry]

It turns out that the nets in question came from net distributors with shoddy follow-up practices; GiveWell suggested Against Malaria instead of other distributors in part because they saw this issue years ago.

http://blog.givewell.org/2015/02/05/putting-the-problem-of-b... https://www.againstmalaria.com/NewsItem.aspx?newsitem=Net-us...

[tomjen3]

Great find.

To me there are two issues at stake: taking their 90% claim at face value that may very well still leave them a very effective charity.

I am more concerned for the fishing stock. Assume 5% chooses to use their nets to fish with - is the this enough to have a material impact on fishing stocks? Will this effect the community to the point that the rest also have to use these nets to catch enough fish? Even if not, what is the effect of the insecticide?

Your articles seem to be really convincing with usages rate, but unfortunately rather handwavingly with the insecticide.