These items are mostly non-biodegradable & have been responsible for the deaths of many animals, both wild & domestic, either from ingestion or injuries caused through panic, as well as littering the countryside. Releasing them should be a specific littering offence.
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I was riding & found a large metallic pink deflated helium balloon stuck on the gate onto the bridleway which stopped my horse in her tracks. I jumped off, led her towards it, untangled it, rolled it up & put it under a stone to be disposed of when I got back praying all the time that it would not blow off as the wind blowing towards so it would have come straight at us, potentially causing my horse to panic & hurt or even kill herself and/or me.
People can be fined for littering if they throw away an apple core. How can it be legal for these things be released to pollute the countryside?