Synthetic vs. Coal Tar Sealcoating:
The Complete 2026 Comparison

Walk into any conversation among sealcoating professionals and one debate will surface within minutes: coal tar or asphalt-based? Add acrylic sealers into the mix and the conversation gets even more nuanced. Each product has genuine strengths — and real drawbacks. This guide gives you an objective, science-backed comparison so you can make an informed decision.

The Three Main Sealer Types

1. Coal Tar Emulsion

Coal tar sealers are derived from the byproducts of high-temperature coal processing. They have been used on US pavements since the 1950s and were long considered the gold standard for durability and chemical resistance. Coal tar's dense molecular structure creates an extremely hard, wear-resistant film with outstanding resistance to petroleum products (gasoline, motor oil, hydraulic fluid) — a significant advantage in commercial settings like gas stations and auto repair shops.

How it's made: Coal tar pitch is emulsified in water with clay and other additives. The resulting product is jet black, with a sharp chemical odor. It typically contains 50,000–70,000 mg/kg of polycyclic aromatic hydrocarbons (PAHs).

2. Asphalt-Based (Petroleum) Emulsion

Asphalt emulsion sealers are derived from crude oil refining — the same base material as the pavement itself. Because they're chemically compatible with asphalt, they bond exceptionally well to the pavement surface. They contain PAHs at concentrations of approximately 20–40 mg/kg — 1,000 to 3,500 times lower than coal tar products.

Modern asphalt emulsion sealers, particularly those with 28–35% solids content and polymer modifiers, have significantly closed the performance gap with coal tar over the past decade. They are the most widely used residential sealer in the US today.

3. Acrylic / Synthetic Polymer

Acrylic sealers use water-based synthetic polymer chemistry rather than petroleum byproducts. They are completely free of PAHs and other petroleum contaminants, making them the most environmentally benign option. High-quality acrylic sealers offer the longest service life — often rated 3–5 years per coat versus 2–3 years for petroleum-based products — and excellent UV, chemical, and abrasion resistance. The tradeoff is cost: acrylic sealers typically run 30–50% more per square foot than coal tar or asphalt emulsion products.

Head-to-Head Comparison

The Coal Tar Safety Issue — What the Science Says

This isn't a fringe concern. The US Geological Survey (USGS) has conducted extensive research on coal tar sealcoating since the early 2000s. Key findings:

• Parking lots sealed with coal tar have PAH concentrations in adjacent soil that are 65 times higher than those sealed with asphalt emulsion
• PAH concentrations in house dust from residences adjacent to coal tar-sealed parking lots are 25 times higher than in houses near unsealed or asphalt-sealed lots
• Runoff from coal tar-sealed surfaces is toxic to aquatic invertebrates and fish at concentrations found in urban streams
• PAHs from coal tar sealcoating have been identified as a significant source of PAH contamination in US waterways and sediments

PAHs include several compounds classified by the EPA as probable or possible human carcinogens, including benzo[a]pyrene, one of the most potent known carcinogens. Children playing on or near coal tar-sealed surfaces face the highest exposure risk.

Where Is Coal Tar Banned?

The regulatory landscape continues to evolve. As of early 2026:

Statewide restrictions:

• Minnesota — Full statewide ban (2006), one of the first in the nation
• Washington State — Effectively prohibited via Department of Ecology regulations
• New Hampshire — Statewide ban enacted

Major municipal bans (partial list):

• Austin, TX (2006) — First major US city to ban coal tar sealers
• Washington, D.C. (2009)
• Chicago, IL and Cook County
• Madison, WI and Dane County
• Ann Arbor, MI
• Portions of the Chesapeake Bay watershed (MD)
• Multiple Oregon municipalities
• Several Colorado Front Range cities

With dozens of additional jurisdictions under active consideration, the trend is clear: coal tar's era in residential sealcoating is ending. Many contractors have already transitioned their entire business to asphalt-based or acrylic products.

Asphalt-Based Sealers: What to Look For

Not all asphalt emulsion sealers are created equal. Quality indicators:

• Solids content 28–35% — Higher solids mean more protective material deposited per coat. Avoid anything below 25%.
• Polymer-modified — Look for "polymer-modified" or "rubberized" formulations, which significantly improve flexibility, adhesion, and wear resistance.
• Reputable brands — SealMaster, Neyra, GemSeal, and Bonsal American produce commercial-grade asphalt emulsion sealers widely used by professional contractors.
• Specified dilution ratio — Quality contractors follow manufacturer specifications for dilution. Ask your contractor for the product data sheet.

Acrylic Sealers: When Are They Worth the Extra Cost?

Acrylic sealers make the most sense when:

• You're in a state or city where coal tar is banned and want maximum durability
• You have a newer driveway in excellent condition and want the longest possible protection interval (3–5 years vs. 2–3)
• You have a decorative or colored asphalt surface
• You're sealing a play area or spaces heavily used by children
• Your driveway has high chemical exposure (vehicle oil drips, fertilizer runoff)
• Environmental impact is a significant personal consideration

What to Tell Your Contractor

When getting quotes, specify your sealer preference upfront. Ask:

1. "What sealer product do you use — brand and product name?"
2. "Is it coal tar, asphalt-based, or acrylic?"
3. "What is the solids content as applied?" (accounting for any dilution)
4. "Is this product legal in my city/county?"

A contractor who can't answer these questions clearly, or who resists answering, is a red flag. Reputable professionals know their products thoroughly and are happy to discuss them.

Our Recommendation for 2026

For the vast majority of US homeowners: choose a high-quality polymer-modified asphalt emulsion sealer (28–35% solids, 2 coats) from a reputable contractor. This delivers excellent protection, is legal everywhere, is safe for your family and the environment, and costs no more than coal tar.

If budget allows and longevity is a priority, a premium acrylic sealer is worth the additional cost — particularly if you want to extend your re-sealing interval to 4–5 years.

Coal tar is an increasingly legacy product with documented health and environmental risks, shrinking legal availability, and no meaningful performance advantage over modern alternatives for residential use. We do not recommend it for home driveways.