ASA report used data from Facebook, Instagram, Snapchat, Twitter and YouTube.
The watchdog says new guidance is needed to help businesses get their advertising right amid increased focus on preventing climate change.
ASA chief executive said there is ‘simply no excuse’ for poor labelling.
Gambling, alcohol, e-cigarettes and HFSS ads were found on media popular with children by the ASA operation.
UK watchdog said two ads were 'misleading, irresponsible and likely to cause fear without justifiable reason'.
Fuel giant claimed in ad that customers could 'drive carbon neutral' if they shopped at Shell.
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