The Sydney Institute of Marine Science (SIMS) is a partnership of four Sydney universities at Chowder Bay. Donations fund research, research training and community engagement; projects have included microplastics in Sydney rock oysters. Its 2025 annual report is on the site.
Honest caveat: there is no dedicated plastics fund, so ask for your gift to be directed. The donations page states gifts of $2 or more are tax-deductible in Australia; the Australian Business Number is not shown, so confirm on the Australian Charities and Not-for-profits Commission (ACNC) register if you need a receipt for a large gift. (We could not open the University of Newcastle or Macquarie giving pages, so they are not listed.)
How to start: sims.org.au/donations