Picric Acid - Is it safe?

There are concerns over Picric Acid in the fly fishing industry. Semperfli Picric Acid is laboratory manufactured for them specially and is safe for dying of fly tying feathers, furs and synthetics.
Picric Acid crystals or 2,4,6-trinitrophenol were dangerous and used for explosives, indeed the navy used this to fire canons pre 1916. It was first mentioned in alchemical writings of Johann Rudolf Glauber in 1742. The picric acid would form very sensitive picric salts within days of filling the shells and would often detonate from the shock of firing. Lacquering the insides of the shells and spraying them with a turpentine / starch solution neutralized the picric acid and prevented it from forming picric salts. Today we use diluted picric acid and store this in plastic containers. We do not use metals even for agitation and it is perfectly safe. 

Pre-dyed products

Semperfli have pre-dyed some natural materials so you dont have to do all the work or worry about the mess! These materials have been left in the dye until they have visibly changed colour, some products this can take a couple of hours (Pheasant Tails / Peacock Herl) others for a truly deep colour penetration the materials are left for many hours, sometimes overnight dependant on the concentration (Deer Fur / Hares Masks).

All products are washed in clean running water until no dye is left visibly coming off the product. Even though this is done there can sometimes be some colour transfer and this is completly normal and harmless. However... please do not ingest the products! If your pets does ingest any, keep an eye on them for 24 hours, if you are concerned please take them to your vets.

5% Solution - Dye Kit

If you fancy getting your hands dirty why not try the dye at home kit! 100ml bottle supplied with Safety Data Sheet and gloves. If you don't use the gloves, although the product is safe it can make you look like you have smoked 60 cigarettes per day for years!

Additional items you will need:

  • Plastic bowl
  • Plastic tools (large cooking ladel / tongs)
  • Safety glasses
  • Protective clothing - Plastic apron is best as it you have soft material coverings it will stain them and seap through
  • 2 liters of water
  • Drying space - airing cupboard / drying rack / hairdryer (somewhere where there is air movement)

Health and Safety

It is vitally important that you keep the dye solution out of reach of children as it looks like orange cordial / squash. If on the rare chance that it is ingested by a child / pet please seek medical advise, remember to take the bottle with you as this has all the information of the composition on the ingredients:

Name EC# CAS# Content Classification
Picric Acid 201-865-9 88-89-1 1-5%

Expl. 1.1; Acute Tox. 3;

H201 H301 H311 H331

E; T; R3 R4 R23/24/25

PROTECTIVE EQUIPMENT - HAND PROTECTION Use protective gloves.  The most suitable glove should be chosen in consultation with the gloves supplier, who can inform about the breakthrough time of the glove material.
EYE PROTECTION Wear approved, tight-fitting safety glasses where splashing is probable.
RESPIRATORY EQUIPMENT Self-contained breathing apparatus where high splashing is likely.
OTHER PROTECTION Provide eyewash station.
HYGIENE MEASURES DO NOT SMOKE IN WORK AREA! Wash at the end of each work shift and before eating, smoking and using the toilet.  Promptly remove any clothing that becomes contaminated. Wash promptly with soap & water if skin becomes contaminated.
Semperfli have the full MSDS (Materials Safety Data Sheet) contact Semperfli if you require a copy (https://www.semperfli.net/contact.html). As with any chemicals take care and you will be safe.

The Essential Fly & Semperfli Fly Tying Materials Limited accept no warranty or risks for its usage.

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