Running across this article about 19 things you are not supposed to put in the trash, not only are you not supposed to throw these in the trash, you are not supposed to throw them in the ocean. Guess what you can find almost all of the 19 items trashed in the ocean.
1.) Batteries –Batteries are chemical laden, yet they show up on the beach. Flashlight batteries, toy batteries and even car batteries will show up on the beach. Car batteries have been found in beach clean ups
2. Light bulbs Wikimedia.org I do not find alot of ‘lightbulbs’ per say on the beach, but have found flashlights (3 a year) and lighted toys with a few lightbulbs. It is also not an unusual sight to see Fluorescent light bulbs in the trash, as quite a few residents will put them there. Cheap suckers will not go to FREE recycling events to dispose of them. Light bulbs are full of toxins and will break down and end up in the ocean and our drinking water.
3. Unused or expired prescription drugs –I do not want to even tell you how much ‘medicine’ I find on the beach. I will include in this category: Sunscreens, lip balms, lotions, contact lens solution, toothpaste, toothbrushes, assorted allergy medications, aspirin, condoms (new and used), tampax (new and used), shampoo, hair gel, chapsticks, cosmetics, antiseptics, bandaids (new and used), coconut oils, palm oils and more. These were all found on the tide line, waiting to be washed out to sea and eaten by marine animals.
4. Aerosol cans: One of the worst things for the environment is aerosol cans. During the summer everyday at least 5 of those spray on sunscreens ( expensive and worthless). I have found Spray Paint (Black and Red) and spray on deodorant on the beach. Then you have silly string, which pollutes in two ways.. the string itself and the can. These aerosol cans can be recycled in San Diego.
5. Computers and electronics: Electronics are also another toxic laden device. Would you eat Mercury, Lead, Beryllium, Cadmium? Aside from cells phones, ear buds, fit-bits and Go Pros, broken digital watches and other electronic devices are not unusual on the beach. E-Waste is a growing problem globally. While some companies such as Dell are mining the gold to make jewelry , most people just throw them away in the trash. or the ocean for that matter. 
According to Chanel Pro Network 70 million smartphones are lost each year, with only 7% recovered. Not that a huge percentage is lost in South Mission Beach, but in the summer.. it is not unusual to find people searching for their lost cell phones in the sand. I usually average 20 a season, while hearing about lost cell phones on Next Door is a weekly post.
6. Hair (human and pet) This was on his list, but the only hair on the beach is from living animals, hairbrushes and dead animals. Hairbrushes and combs are found weekly.
7. Bacon fat or cooking oils: This was also on this list, but many people BBQ and of course the drippings land in the sand.
8. Paints and stains: Why would someone leave paint? We have FREE paint recycling in San Diego. All you have to do is leave it at a Paint Store. Within our zip code, we have at least 5 paint leave off locations. While not common, one does find it on the beach. I now have red and black spray paint found on the beach.
9. Lawn and garden chemicals: It is bad enough that people use Round Up, worse when they use it by storm drains. Not usual to find on the beach, but plastic plant containers are pretty usual, as many people reuse as beach toys.
10. Lighters and Lighter Fluid– One of the most common pieces of trash, that should never be put in the trash and yet is. They can be found on roadsides, in parks and on the beach. A few things that are so bad with this aside from the highly toxic and flammable liquid. They break apart and the little pieces are eaten by marine animals. They add to plastic pollution
11. Brita Water Filters: These should not go in the recycle bin, but they can be recycled. See Brita for stores. I do not believe I have ever found one on the beach.
12. Glass thermometers: Hypos- Needles have found, but most thermometers are broken apart. Not a usual find. They should never be thrown in the trash because they contain mercury. See the EPA for more information.
13. Plastic bags (including Ziploc storage bags) I can not even tell you how many plastic bags in general are found on the beach. Ziplock Bags are an Easy Twenty. Add in reusable bags, plastic bag packaging and it can come up to 100 plastic bags a day. Most of these bags are washed out to sea. More information on recycling plastic bags at Plastic Film Recycling
14. Cleaning supplies: The biggest cleaning supply item I find is Disinfecting wipes, which are not sustainable and are harmful to the ocean and marine life. I find between them and napkins over 100 a day. You really do not need them and in fact will not help build up important immunities. Sometimes large Clorox bottles will wash up.
15. Cosmetics Conventional cosmetics contain chemical substances that are not removed by water treatment, so flushing them is detrimental to the water supply. Even when empty, cosmetic containers can’t be recycled due to the blend of materials that they’re made of.Fortunately, there are cosmetic recycling programs. Take containers from used cosmetics — regardless of brand — to any Origins store (or Origins counter in a department store), or Aveda, M.A.C, and Kiehl’s, and they’ll be recycled responsibly.
16. Tires: Have never found a car tire, but have found bicycles, bicycle tires, toy tires and other rubber accessories. Currently it is illegal to throw tires in the trash in 48 states. Tires are pretty usual in any beach, river or watershed clean ups:
- 2016: Alaska: Tires were picked up with 22,000 pounds of refuse from 50 miles of coastline. (NPS)
- 2016 Ventura County, California: 45 Tires were picked up along with 11,846 pounds of litter, or 5.9 tons (VC Star)
- 2018: New Jersey Clean up with a huge tire (NJ.com)
- 2016: Seattle, WA: Tire Buyer hits beach to collect old tires
17. Old appliances: Any appliance is bad for the environment. I found a fridge on the beach in Bucerias, Mexico, have assorted other appliances such as hair curlers, lid openers. In 2017 a fridge was found surfing in Brazil. (Euro News) I believe and then again found in April of 2018 a Refrigerator on the beach in Pinellas County, Florida. Finally in April of 2017 a Refrigerator was fished out out tangled fishing lines in Hawaii (West Hawaii Today) In 2015 in Port Charlotte, Florida 28 Refrigerators were cleaned up in the Annual Coastal Clean up. TV sets have been found, as well as computers. The Long Run reported their September 2015 Cleanup included: 97 TV sets and 28 refrigerators. Dana Point, California, a new flat-screen TV was pulled from the bottom of Dana Point Harbor
18. Unexploded fireworks: Plenty of leftover fireworks will show up on the beach
19. Glue and adhesives contain toxic chemicals Nothing is more toxic that styrofoam 
As to finding car batteries, never, but have found the bottles of motor oils or car parts. Car parts and batteries are found yearly in Beach Clean ups. 
- People in Pennsylvania were cleaning creeks in inland locations and pulling out appliances, car parts, car batteries and items that you just couldn’t dump on the beach without someone seeing you,” said Nicholas Mallos, (Source)
- A red octopus had squeezed its way out of the vent cap of a car battery that was dredged up by divers from the water around Harford Pier. Four of the slimy sea creatures had made their home in the discarded battery, (San Luis Obispo, CA)
There you have it.. the ocean is the world largest garbage dump.. unfortunately.