In your analysis, start by describing the product(s): the what, how much and who, following the IMP framework.
Then describe the impact by linking studies on this product and its general impact, making a comparison with competitors and industry average, when relevant. You must mention the direct impact of the product and how significant it is. You can use studies as proxies. Learn more in the article Step 5: Assess scale and value.
A specific issue, yet a relevant one, is treating a single angle. For example, household products may be toxic to human health and biodiversity. In this scenario, it is essential to stick to one specific angle on this topic. To learn more about granularity, check out this article.
Biodiversity can also be harmed from products in various ways. This links to different SDGs, such as pesticide and fertiliser runoffs leading to aquatic pollution, and pollution from chemicals and other hazardous waste.
In your analysis, make sure to describe the scale of the impact by taking into account:
1/ The breadth of the impact
Is the impact local, national, or global?
How many people are concerned? Thousands? Millions? Billions?
As a rule of thumb, if it affects at least 1 million people, it is considered significant. Although, please bear in mind that this is not always the case, as, at times, it could be considered unfair to expect an impact to touch that many lives. Thus, this is flexible.
2/ The depth of the impact
Is the life of people concerned deeply affected, or does the issue just marginally impact them?
Are the changes brought by the issue profoundly changing society or the planet?
3/ The persistence of the impact