[pct-l] Bathing on the trail

[Gary Wright]

On Sep 2, 2009, at 2:05 PM, dave encisco wrote:
> Excellent advice! And if you're one of those who uses Deet and/or  
> sunscreen during the day and then either goes for a swim in a lake  
> or wash yourself off in a river...shame on you. You've just released  
> zinc oxide, or titanium dioxide, or N N-diethyl-m-toluamide into a  
> water habitat. I'd rather see someone urinate (inert anyway) in the  
> stream than see someone washing off in the stream. This and carrying  
> out your toilet paper are my pet peeves, although leaving your  
> toilet paper behind is insignificant compared to releasing N N- 
> diethyl-m-toluamide into the water.


Just to clarify my jump in a lake or creek comment:

I was assuming that these were sufficiently large lakes or creeks that  
any hiker residue would be  negligible relative to the volume of  
water. Immersing yourself in springs or other low-volume/pristine  
water sources isn't cool.  Soap/shampoo products should not be used in  
backcountry water sources and arguably should be avoided even when  
rinsing off away from the actual water source.

I do think hikers should should be expected to pack out all their  
trash including TP.

As for sunscreen/deet contamination, I would guess that 99.9% of  
hikers are guilty of this. How many of us rinse off before fording a  
creek in the Sierra?  Even if you were careful to do this 200 ft away  
from any water source you are still introducing the chemicals into the  
environment.

At this point I'm pretty skeptical that typical sunscreen/deet use has  
any measurable impact on the backcountry environment (mainly due to  
the ratio of water to chemicals).  A little googling revealed this:

> Due to the manner in which DEET is applied and used, it is not  
> likely to affect terrestrial wildlife or aquatic organisms adversely  
> (EPA 1999).

That quote is from: <http://www.atsdr.cdc.gov/consultations/deet/environmental.html

Gary Wright (Radar)