Vehicle emission, pollution and foraging.

[bernsad]

Hi All,

I was watching a nice stand of weeds flowering alongside a busy road the other day. The girls were harvesting like crazy and I was wondering what effect all the vehicle exhaust would have settling on the flowers and how much contamination of the honey would occur. What are your thoughts on this and can anyone point me in the direction of further information or research please?

Thanks
B

[AllenF]

It can't be much worse that smog on 90 plus temp days.  And if the roadways are so bad, it is only a small percentage of the honey collected.   

[bernsad]

I just remember reading a long time ago about increased levels of lead and heavy metals found in the soil alongside major roads. Now obviously they don't use much lead in petrol anymore but I still wonder about the level of contamination.

Also, over here in mid-late winter, a good stand of wild turnip flowering might be one of the few things producing pollen at the moment and so forms a good part of the forage brought into the hive.

[BlueBee]

Good question.  I recall reading a paper some time ago that the emissions from vehicles tends to settle inland from the road due to the high temps of the exhaust raising when they come out of the engine. Luckily Tetraethyllead has been banned here for boosting octane in passenger vehicles for a long time.  (We now use food to boost our octane in the USA!)  No idea how long tetraethyl lead stays in the environment or the lead that leaches out of all the paint people used for 100 years on their houses.

The primary pollutants from modern spark engines are oxides of nitrogen (N2 in air getting oxidized when combustion is too hot), carbon monoxide (combustion too cool), and unburned hydrocarbons (from quench zones).  While bad, these things are gasses and I’m not sure they ever settle down on anything.  The real nasty stuff is the exhaust from diesel engines.  You get all kinds of carbon chain compounds from a diesel engine with many of the particulates being known carcinogens. 

http://en.wikipedia.org/wiki/Diesel_exhaust

[bernsad]

Thanks for the article BlueBee. Can I hazard a guess that you are an industrial chemist or something similar?

[AllenF]

My truck don't blow black smoke.   No carbon exhaust anymore.   That's to the fed government my engine use a diesel particulate filter (DPF) to capture carbon particles and then intermittently burn them using extra fuel injected directly into the filter. This prevents carbon buildup at the expense of wasting a large quantity of fuel and lowering my MPG.   (At least until I hit 100,000 miles and off it goes)   

[wayne]

  There was alot of lead in older cars. Lead was melted and used in the factories as body filler. To balance tires and as shims between parts as well as in the fuel. Studies and incidental findings have shown particles of lead along ever street and road in the country.
  However, I have never read anything on whether lead is absorbed by plants, or present in flowers or fruit.

[bernsad]

I was wondering about particulates settling on the plants/flowers and maybe getting dragged back to the hive with the bees. Does this then just get transferred to the honey?