From October 2009

**Q. I’m a little confused with the actual purpose for an MSDS sheet.  If the only requirements are to put on the sheet what is known to the best of their knowledge than what authority if any does it have?  If company “A” purchases a chemical from company “B” and obtains with it an MSDS sheet that says under disposal requirements: “none listed”, can company “A” in good faith dispose of the chemical down the drain even though the chemical is actually hazardous?  If the EPA or OSHA traces the improper disposal of this chemical back to company “A” who is the one responsible?  Can company “B” be released of all legal responsibility?  That just doesn’t seem to fair.
A. You have a foot in each of two different worlds.  OSHA=worker safety;  EPA=hazardous waste.  You could not get away from the EPA hazardous waste issue by using the bad MSDS.  For waste, you would always need to go back to the EPA regulations with their criteria and lists. 

*Q. I also read under SIRI’s database that employers are not required to provide their employees the MSDS that was given to them by the manufacturer of a certain chemical.  They can create their own MSDS and give it to the employees.  What protections do the employee’s have to ensure that the information they receive is accurate and reliable?
A. None, except OSHA enforces this kind of paper violation very well.  As a practical matter, the employer could not ignore the hazards listed on the suppliers MSDS sheet, since the employer would “know” about the hazard.  High end employers will generally add things to MSDS sheets for chemicals that they deal with - to make them more complete.  On the other hand, some employers, like a materials handling warehouse, may have thousands of chemicals that pass through.  There the employer is lucky to be able to keep a copy of whatever the supplier or shipper gives them.

*Q. The muddiest thing for me was your answer to the question on whether lipophilic, non-polar and hydrophobic are synonyms…I was good until the lipophilic term was brought in.  Doesn’t lipophilic mean “fat-loving”?  Is this in reference to chemicals in the body?  But isn’t there water in body fat?
A. Lipophilc doesn’t necessarily mean body fat, but you’re right on the origin of the word.  In the body there are fat storage globules in things like liver cells (hepatocytes). Fat storage cells (adipocytes) that are essentially all fat storage globule.  A lipophilic chemical will partition out of the body fluid (which is mostly water) and into the fat.  This partitioning is governed by the laws of chemistry and happens without specific system in the body to move the chemical.  Most hydrophobic substances are also lipophilic – not many other places to go.  But not all lypophilic substances are hydrophobic.  Some, like methanol, are both lipophilic and hydrophilic.  Actually, when you use the words, they generally have a relative meaning, “X is more lipophilic than Y.”  “Polar” and “nonpolar” are likewise usually used relatively.  Some useful molecules have a polar end and a non-polar end – some have “polar sites” in an otherwise non-polar molecule. 

End new Q&A.

**Q On the subject of MSDS, I find it hard to believe that there isn’t a standard database of official MSDS that is produced by a single agency, like the EPA for example.  It seems ridiculous and dangerous that there are such large discrepancies in the documents found on the web.  Why isn’t there such a program? 
A. The law lays all that responsibility on manufacturer or importer and requires the employer to provide them to the worker.  There are indeed services that will provide employers with a database of thousands of MSDS sheets.  However the fine print in the contract will say “your mileage may differ,” or other exculpatory language. 

*.Q. I found it interesting to learn about the differences between the OSHA PEL’s and the ACGIH TLV’s.  It seems odd that the two limits would be different, especially when the health of individual humans is at stake.  I guess it disturbs me a little that OSHA’s process of setting PEL’s would be so politicized.  While I would hope that companies would want to be responsible and support lower, healthier limits, I also realize that they are making those chemicals to turn a profit and lower limits could potentially damage those profits.
A. Yes, money gives them an incentive to fight, but often the adverse health effects are really speculative, not facts.  Often it is the manufactures of the chemicals that fight, afraid that a more stringent limit will force their customers to try other products.

* Q. I am still a little foggy on how to determine the best air monitoring device.  Perhaps that is more of an Industrial Hygienists specialty but I’m not sure I feel confident that I’d know that a specific media and contaminant warrant this type of monitoring device.  Are there rules of thumb?  This contaminant doesn’t work for this type of device?
A. The take home message is that you need to know what you are monitoring, then select the right device based on the warnings you need.  Once you know that, any of the main manufacturers will be happy to discuss which of their products will work for you.  Many types of monitors have the same basic electronics and set case, but have a sensor that one changes out for the different chemicals.  An important concept of any monitor (or lab equipment) is that of calibration.  All need to be calibrated from time to time. 

* Q. If the TLV is a recommendation and PEL is the law, in the case TLV’s are more conservative than PEL’s,  what motivates industry to purchase and follow the TLV’s since in most cases companies prefer more lenient standards?
A. An ethical industrial hygienist will follow the TLV if it is more conservative.  So if an industry hires an IH to examine a situation where the exposure is over the TLV but below the PEL, the report will come back explaining that and recommending the workplace exposure be reduced below the TLV.  The industry may or may not follow the recommendation.  But today, most reputable stable industries would follow the recommendation.  Especially since such IH studies usually follow some sort of worker complaint, lawsuit or whatever.