Natural grass is generally safer than artificial turf for most athletes, but the answer depends on which risks you’re comparing. Grass surfaces produce fewer knee ligament injuries in football, run significantly cooler in warm weather, and cause fewer skin abrasions. Artificial turf has its own advantages, including more consistent footing in wet conditions and no exposure to pesticides. Here’s how the two surfaces compare across the safety factors that matter most.
Knee and Ligament Injuries
The biggest safety gap between grass and turf shows up in knee injuries, particularly tears of the anterior cruciate ligament (ACL). Among NFL players, ACL sprains are 67% more common on FieldTurf than on natural grass. College football players at the Division II and III level experience ACL injuries at 1.63 times the rate on turf compared to grass.
The pattern isn’t universal across all sports, though. In professional men’s soccer, ACL injury rates are actually slightly higher on natural grass (1.16 per 10,000 athlete exposures) than on artificial turf (0.92 per 10,000). Female soccer players show the opposite trend: an 18% higher ACL injury risk on artificial turf compared to grass. The difference likely comes down to how cleats interact with each surface during the cutting, planting, and pivoting movements specific to each sport.
The mechanism behind these injuries involves how much grip the surface provides when a player’s foot is planted and their body rotates. Artificial turf fibers can “grab” a cleat more consistently than grass, which may deform or give way under force. That extra grip is great for acceleration but creates more torque on the knee when a player changes direction. Research on shoe-surface interaction shows that wet versus dry conditions significantly change rotational forces, and athletes wearing shoes not designed for the surface they’re playing on face the most extreme friction values.
Surface Temperature
Heat is where artificial turf performs worst. Synthetic surfaces absorb and retain far more solar energy than grass, which naturally cools itself through evaporation. According to the Washington State Department of Health, artificial turf temperatures can range from 35 to 85 degrees Fahrenheit hotter than natural grass on the same day.
On a summer afternoon when grass sits at a comfortable 80°F, turf can reach 140°F or higher. That’s hot enough to cause skin burns on contact, and it raises the air temperature in the breathing zone just above the surface. For young children, who are shorter and closer to the ground, this effect is more pronounced. Heat-related illness, including heat exhaustion and heat stroke, becomes a real concern during summer practices and games on turf fields, especially in southern climates.
Turf Burns and Skin Injuries
Anyone who’s slid on artificial turf knows about turf burn. The synthetic fibers are more abrasive than grass, and a slide or tackle can strip away layers of skin in a way that rarely happens on a natural field. These abrasions aren’t just painful. They create open wounds that are vulnerable to bacterial infection, particularly in shared athletic environments where players are in close physical contact and sweating heavily. Grass can still cause scrapes, but the surface is softer and the soil beneath it compresses on impact rather than grinding against skin.
Chemical Exposure
Artificial turf, particularly fields filled with crumb rubber made from recycled tires, has raised concerns about chemical exposure. The rubber granules contain heavy metals (arsenic, lead, cadmium, chromium, and mercury) and compounds called polycyclic aromatic hydrocarbons, or PAHs. Zinc is found in especially high concentrations because it’s used in the tire manufacturing process.
The turf blades themselves can contain PFAS, sometimes called “forever chemicals,” which have been linked to liver disease, kidney disease, immune problems, and cancer in other exposure contexts. However, research published in Environmental Health Insights found that the PFAS present in artificial turf are not prone to migrating from the material in ways that would affect human health.
As for the crumb rubber, simulated exposure studies have concluded that PAH concentrations from turf infill pose minimal to no health risk through oral, skin, or inhalation routes. No epidemiological studies have directly examined whether people who play on, install, maintain, or dispose of synthetic turf develop higher rates of cancer or other diseases. The existing evidence suggests the chemical risk is low, but the research base is thin. No one has done the kind of long-term tracking study that would settle the question definitively.
Pesticides on Natural Grass
Natural grass isn’t chemical-free either. A survey of athletic field managers found that about 65% applied pesticides to their fields, with herbicides being the most common (used on 57% of fields). These chemicals are designed to kill weeds and insects, and they can linger on the surface where athletes roll, slide, and sit. Children are at particular risk because of their smaller body size and tendency to put their hands near their mouths during and after play. The health effects depend on which products are used and how recently they were applied, but the exposure is real and often unregulated at the recreational field level.
This is one area where artificial turf has a clear safety advantage. Synthetic fields require no herbicides, pesticides, or fertilizers, eliminating that exposure entirely.
Impact and Concussion Risk
Both surfaces need to absorb impact when a player falls or is tackled. The standard measurement for this is called Gmax, which measures how much force a surface transmits during an impact. A Gmax value of 200 or above is considered the threshold where life-threatening head injuries may occur. Fields with an average Gmax above 170 need maintenance to soften them.
Well-maintained artificial turf with adequate infill depth generally passes these thresholds, and so does healthy natural grass with a good root structure and soil base. The problem arises when either surface is neglected. Compacted, dry natural grass can become dangerously hard, and worn turf with depleted infill loses its shock absorption. The safety of either surface depends heavily on maintenance. A poorly kept grass field can be harder than a well-maintained turf field, and vice versa.
Which Surface Is Safer Overall
For football players concerned about knee injuries, grass is meaningfully safer. The 67% increase in ACL sprains on turf in the NFL represents a substantial risk difference for a career-altering injury. For athletes playing in hot climates, the temperature gap alone can make grass the safer choice. And for anyone prone to sliding or falling, grass causes fewer and less severe skin injuries.
Artificial turf wins on consistency. It doesn’t develop divots, muddy patches, or bare spots that can catch a foot unexpectedly. It eliminates pesticide exposure. And it remains playable in conditions that would make a grass field a muddy, uneven hazard.
The chemical concerns around crumb rubber and PFAS, while understandably alarming, haven’t been supported by direct evidence of harm at the exposure levels athletes actually experience. That said, the absence of long-term studies means the question remains open rather than answered.
If you’re choosing between the two for a youth sports program or evaluating where your child plays, the most important factor may not be the surface type itself but how well it’s maintained. A neglected field of either kind is more dangerous than a well-kept one. Beyond maintenance, the evidence tilts toward natural grass as the lower-risk option, particularly for sports that involve heavy cutting, pivoting, and ground contact.