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I sent an email requesting the GFAJ-1 strain from Oremland's group, and received a Materials Transfer Agreement form from them. I filled it in, found and filled in the other form that our local bureaucracy requires, and sent them both on to the UBC people who sign such forms. Provided they don't see any complicating factors (fingers crossed that the lawyers don't get involved), it should be signed in a day or so and them I'll have a 2-4 week wait to receive the cells.
I also contacted our Chemical Safety office about the rules and regulations and general safe practices for working with and disposing of arsenic. First I was just given weird information about disposal (is arsenate really volatile? If so, why not disinfect with iodine?), and when I asked for more information all I got was a form-letter list of generic advice. I've pasted the correspondence below.
Luckily a colleague might be investigating the effects of arsenic on bioremediation, and maybe she can help me with the safety issues.
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To: Chemical Safety contact person
Subject: Advice on experiments using culture media containing arsenic
Hi,
I'm considering doing some experiments where I will culture bacteria in a medium containing 40 mM arsenate. Are there specific safety procedures and disposal regulations I should be aware of?
The cultures will be at room temperature, not shaken and in fairly small volumes (initially 10 ml in screw-cap glass tubes,) The bacteria are not pathogenic.
Thanks very much,
Rosie Redfield
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Hello Rosie,
The challenge with this experiment is that you end up with mixed microbiological (risk group 1 from what you indicated) and chemical waste. In this case my recommendation will be first to kill the bacteria so the mixture will no longer be biohazard, since you cannot autoclave it and bleach is incompatible with the arsenate, I will recommend treating it with ethyl isopropyl alcohol 70-85%. After this treatment the mixture could be considered sodium arsenate, ethyl isopropyl alcohol mixture and can be disposed of as chemical waste. You will have to go online through our chemical waste inventory system, to request approval for disposal, indicating the chemical name and percent of these chemicals in the mixture, and follow the chemical waste disposal procedure.
Let me know if you have any question or if you need additional information.
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Hi (name redacted),
I definitely need more information, about handling materials containing arsenate as well as about disposal.
Can I not autoclave any solutions containing arsenate? Where can I find information about what I can and can't do? What are the concentration or volume issues?
Thanks,
Rosie
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Hello Rosie,
- -Information about handling this material specifically you will find in the material safety data sheet for the specific product you are using
- -General information for safe handling of chemicals can be found in the Laboratory Chemical Safety Manual
- http://www.riskmanagement.ubc.ca/health-safety/chemical-safety/chemical-safety-manual
- -Autoclaving the mixture can result in generation of toxic vapors
- -As for the disposal, the specifics for your mixture are indicated in the e-mail below. In general all hazardous waste procedures are available on-line http://www.riskmanagement.ubc.ca/sites/riskmanagement.ubc.ca/files/uploads/Documents/manual8709.pdf
- -As for concentrations and volumes to be used, our recommendation is as low as practically possible. But once you define your experimental protocol, you will need to re-assess the required safety precautions (personal protective equipment etc.), based on the concentration and volume you are going to use
- -All the above info and more (other than the details provided below) is available through the UBC Laboratory Chemical Safety Training that is now offered online.
Arrrggh!
ReplyDeleteI've dealt with similar issues with safety offices; they encourage a culture of "Please refer to your MSDS, where everything is explained". The employees of these offices may even posses undergraduate degrees in chemistry, but somehow, you often can't converse with them at a common sense level.
I suppose being a safety officer wouldn't be that exciting for most researchers, but you I wish they would just be able to formulate policies and procedures based on more just than what the MSDS says.
You run the risk of people implementing ad hoc policies, but this type of response just doesn't really encourage critical thinking when it comes to safety.
I'd go with the suggestion of one of the commenters on your experiment: run gels at each step to see if the DNA is unstable.
ReplyDeleteI'm asking several people here what they would do to detect arsenic in DNA. I should have some answers by next week, one of them has a whole building full of hi-tech equipment for similar purposes.
But I'm sure you have someone like that on your campus, too?
I suggest that you also try to grow a more straight forward Mono Lake bacteria as well, such as one of the dissimilatory As-reducing halophiles that Oremland's group has published on extensively in other Science papers. Growing extremophiles is not as easy as growing E. Coli. Salts at >60 g/L and pH 9.8 required for these bugs can present a lot of unanticipated challenges for downstream molecular and analytical work. Good luck.
ReplyDelete@anonymous: If I can't readily get GFAJ-1 growing nicely on the phosphate-based version of the medium the paper specifies, I'll know that I'm out of my depth. At that point I'll leave the whole mess for someone else to test.
ReplyDelete