"ADBAC (benzalkonium chloride) is highly toxic to fish (LC50 = 280 μg ai/L), very highly toxic to aquatic invertebrates (LC50 = 5.9 μg ai/L), moderately toxic to birds (LD50 = 136 mg/kg-bw), and slightly toxic to mammals (LD50 = 430 mg/kg-bw). Benzalkonium chloride solutions of 10% or more are toxic to humans, causing irritation to the skin and mucosa, and death if taken internally."
Gee, I bet that's why you can't buy any on e-bay! LOL (dangit)
It's also the stuff we spray on our kids' scraped knees (i.e., Bactine). You have to take some of the MSDS warnings with a 'grain of salt'. Speaking of, look up the MSDS for good ole NaCl
if you want a laugh. "mutagenic, do not ingest, wash off skin with soap and water" etc.,
. Sorry to resurrect this old thread, but I am actually using some benz alk right now on some persistent cory funk. I got a couple metae from the LFS a few months back and after a couple days I noticed one of them had what appeared to be excessive slime. It got worse over time (spread on that cat, plus a little fin edge erosion), and although it eventually spread to the other metae in the tank, it did not spread to other fish in that tank (some otos) or fish (including cory aeneus) in another tank that shares the same sump. This is a new setup, and everyone is in quarantine together. They got Maracyn I&II, salt/heat/Ich Attack, and fenbendazole (for hydra on plants, but thought I'd mention it). The metae funk has gotten progressively worse, and as I said, spread from 1 metae to the other but not to other fish in the tanks. After some research online, I learned that aquaculturists use benz alk to cut through infections with tenacious slime coat
, specifically because it has that surfactant effect. "Benzalkonium chloride is used as a general antibacterial. It acts as a surfactant, removing excess mucus and slime containing parasites and bacteria from the fish." I've done 2 baths so far (60 min at 2ppm = 1.5ml Bactine in 9.5 cups water). The cats seemed to tolerate it well. I was worried because the bactine also has a topical analgesic (lidocaine), but I monitored the cories' gill vent rate and activity throughout the hour and they did not get sedated. And best of all, the slime coat was quickly and noticeably diminished. I'll post updates as I make progress. Sorry to hijack the net dip thread, but it was the only discussion about benz alk in the forum, and I thought people might like to know that it can be useful for fish.