I suppose, but they did say that they accounted for health and lifestyle factors, so I'm pretty sure that means that it's another cause they hadn't pinned down at the time of the study.

From what I understand, the current theory is chemicals used to make plastic more pliable ended up being endocrine inhibitors, which decrease testosterone production. BPA, and other similar chemicals.

Also, reports that many flame retardant chemicals do the same thing. The law requires that furniture with fabric and curtains and things like that have those chemicals to lower risks of fire. But, those chemical treatments physically break down into dust and we get exposed to them.

There are probably other contributing factors too.

We also see a steep decline in testosterone in dogs. Sure, we could be seeing two unrelated phenomena operating at the same time, but for the moment, we should operate under the assumption that the testosterone declines in dogs and men have a common etiology. If we do so, we rule out a ton of prospective causes.