I'm so curious about the connection between masculinity and polluted places. The particular tension you foreground in this image--the stakes of pursuing recreation in contaminated waters--is also something that emerges in my own field work in Michigan. The Great Lakes and rivers in my fieldsite are tremendously valued for the sport and leisure they enable (like fishing, swimming, or kayaking), although admittedly I haven't tracked as carefully the gendered dynamics of this valuation as your project does. I would love to hear more about two terms that briefly come up in your caption here, sabetsu and mendokusai, and how specifically "discrimination" and "trouble-making" are endured or experiences as gendered acts.
It would help to have more explanation of the significance of this place as a toxic site and how that toxicity pervades it. In addition, it would be helpful to provide a bit more context about your research team and why they are there, as well as why your team was interested in gender and what this says about the place and toxicity. It may also help to shorten the caption to the main points you wish to convey regarding how this image fits within your project on toxicity of place. Including at least a sentence referring to the image itself may be useful for creating more cohesion between the two, with the visual ethnographically opening up the caption or the caption opening up the image, or both at once.