Mercury. Mercurochrome. In whatever form this chemical is used, it has the potential to cause serious allergic reactions in some individuals. Phenylmercuric salts are used in cosmetics and cosmetic glue, which is applied to the skin. Additionally, this compound is used in the agricultural and fungicidal industries, creating even more opportunities for sensitive people to be exposed, according to Your Asthma Treatment. 
What Phenylmercuric Acetate Is
As described by Mallinckrodt Baker, phenylmercuric acetate is a coarse, yellow-white powder. If inhaled, it can cause irritation to the breathing passages of the victim, including sore throat, a tight chest, shortness of breath, headache and breathing difficulties. If it is inhaled in large enough quantities, pulmonary edema can develop. 
Mercuric salts are used in mercurochrome, a common antiseptic. It is also used in some vaginal spermicides, according to Your Asthma Treatment. 
What is Phenylmercuric Acetate Allergy?
Phenylmercuric acetate allergy, or PMA, is a potentially serious condition with reactions ranging from highly itchy rashes up to anaphylaxis, writes Your Asthma Treatment.
People sensitive to any form of mercury (mercurochrome, thimerosal, phenylmercuric acetate, metallic mercury, phenylmercuric nitrate, mercuric chloride or sodium fluorescein) are prone to developing eczematic reactions.
During testing to mercury, researchers (P.A. Galindo, R. Garcia, E. Gomez, J. Borja and F. Fernandez) found that test subjects reacted to some products while they had no reactions to other products. 
What Allergic Reactions Take Place?
According to research carried out and published in “Allergy,” eight research subjects were tested with prick and patch tests to mercurochrome, thimerosal, phenylmercuric acetate and nitrate, mercuric chloride, metallic mercury and sodium fluorescein. Areas of the skin tested with prick testing developed local eczema. Four subjects, who at first tested negative to a mercurochrome prick test, later developed eczema, according to “Allergy.”
Two patients developed anaphylaxis during testing (with mercurochrome). These subjects tested negative to other mercury products being used in testing. The remaining six patients all developed eczema to patch testing using mercurochrome and inorganic mercuric derivatives.
Only two subjects tested positive in patch testing using thimerosal, with only one of these subjects developing a positive patch test to salts of phenylmercury, according to “Allergy.” 
How to Avoid Allergic Reactions
The only reliable way of avoiding an allergic reaction to phenylmercuric acetate is to avoid this product. If you know you’re sensitive to mercury in any formulation, whether as a preservative in vaccines or in cosmetics, read labels, ask questions of cosmetic counter employees and medical personnel and let them know you’re allergic to mercury.
This allergy is one that becomes progressively more severe with each exposure; while you may have a mild reaction at first, you are prone to developing the most severe reaction, or anaphylaxis, which is life-threatening, according to Your Asthma Treatment.  Speak to your doctor about your allergy and ask him what more, beyond avoidance, you can do to protect yourself.
 https://www.jtbaker.com/msds/englishhtml/p3268.htm Mallinckrodt Baker: Phenylmercuric Acetate
 https://www.yourasthmatreatment.com/allergy-cosmetics-metals.htm Your Asthma Treatment: Allergy to Cosmetics and Metals
 https://onlinelibrary.wiley.com/doi/10.1111/j.1398-9995.1997.tb00190.x/abstract;jsessionid=52AD872A9D5682E4C25C5A378AFE6C12.d01t02 Wiley: Mercurochrome Allergy. Immediate and Delayed Hypersensitivity