A relative gave me a new bottle that is free of BPA.. but researching I found out it is a Eastman Tritan which the following articles claim still contain estrogenic chemicals.. I'm still confused by the following articles: https://www.scientificamerican.com/article/bpa-free-plastic-containers-may-be-just-as-hazardous/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3222987/ So does Eastman Tritan copolyester have bisphenol S (BPS)? If not.. what is the estrogenic chemicals present? What bottles or plastic do you use? Maybe the safest thing to use in gym is water jug made of glass?