Question Answer
In the Name of Allah, the Most Merciful and Compassionate
You will find an answer regarding cosmetics and products made with animal ingredients in the following link:
Spreading Impurity
Regardless of the presence or lack thereof of impurities in the lotion, it is highly inconceivable that such impurity would transfer to others after being applied. Therefore ignore any thoughts of impurity spreading.
Other Opinions
Note that though many scholars took a cautious approach to various ingredients and additives in products, others took a more expansive approach regarding incidental ingredients and ingredients that have gone through a chemical transformation.
With that being said, if you wish to be cautious, refrain from direct use of such products. However, it would be best if you did not object to others who choose to use them. You can encourage them to be cautious, but the choice is theirs.
Hope this helps
Allah knows best
[Shaykh] Yusuf Weltch
Checked and Approved by Shaykh Faraz Rabbani