Del. Tom Hucker (D-Montgomery), shown on opening day of the 2012 legislative session with his infant son, sponsored a new law banning arsenic in chicken feed. (Mark Gail/The Washington Post)

A new year means several new laws are taking effect in Maryland and Virginia.

Maryland is banning arsenic in chicken feed, extending the concept of “good time credits” to people on probation and parole, and giving parents a new tool to protect their children from identity theft.

All three measures are among a handful of new laws that take effect Tuesday, in addition to a much higher-profile initiative: the legalization of same-sex marriage.

In Virginia, it will be harder for state and local governments to take property in the name of eminent domain. Voters overwhelmingly approved a constitutional amendment on the issue in November.

Most laws passed during Virginia and Maryland’s 2012 legislative sessions have already taken effect, but several of them had delayed-implementation dates, for a variety of reasons.

The effective date of the same-sex marriage law, for example, was set as Jan. 1 to allow time for an anticipated referendum in November. That took place after opponents gathered enough signatures to force a public vote. Voters approved the new law, 52 percent to 48 percent.

With the new year, Maryland becomes the first state to ban the use of additives containing arsenic in chicken feed, a practice already prohibited by Canada and the European Union.

Last year, Pfizer suspended sales of its drug Roxarsone, an arsenic-based drug used to fight parasites in animals, after a Food and Drug Administration test showed trace amounts of the known carcinogen in the livers of chickens.

Perdue Farms stopped using the additive years ago, and some restaurants, including McDonald’s, do not allow suppliers to use it.

But growers in Maryland, particularly on the Eastern Shore, continued to use stockpiles of the feed after Pfizer suspended it.

Del. Tom Hucker (D-Montgomery), the bill’s sponsor, argued that unknown levels of arsenic have been seeping into the state’s soil and waters for decades through chicken waste, which is often used as fertilizer.

“Consumers should be overjoyed that Maryland is now the first state to end the reckless use of arsenic drugs in farming,” Hucker said Monday. ”Our new law is a big win for consumers and the environment.”

Opponents of the legislation argued that fears associated with the feed additive were overblown.

In Virginia, an amendment approved by voters changed Virginia’s Bill of Rights to say that local governments may seize property only for public uses. It forbids governments from seizing land for economic revitalization if the primary purpose is private gain, job creation or increased tax revenue.

The amendment also expands the definition of a potential loss to a property owner, an interpretation that troubles some local officials. Under the new rules, instead of paying fair market value, a local government must calculate a business’s “lost profits” or the value of “lost access” to the property.

In another nod to property owners, effective Tuesday, insurance agents will have to inform owners if their policy excludes coverage for earthquake damage. The bill came in the wake of a 5.8-magnitude earthquake that struck central Virginia in August 2011. The tremors were felt throughout the D.C. metro region and a large part of the eastern United States.

Starting Tuesday, Maryland joins a growing number of states that allow probationers and parolees to earn “compliance credits” and reduce the length of their supervision.

The legislation was sponsored by state Sen. Christopher B. Shank (R-Washington) and Del. Michael J. Hough (R-Frederick) and won bipartisan support.

The goal of the legislation is to provide incentives for compliance and free up criminal-justice resources for those in need of more stringent supervision. Nevada is considered a forerunner in adopting such policies, which are similar in concept to programs in place in prisons around the country.

Lawmakers, meanwhile, are giving Maryland parents a new tool to fight identity theft under another law that takes effect Tuesday.

Under the law, parents will be able to freeze their child’s credit, with the hope of preventing his or her personal information from being used fraudulently.

If contacted by parents, major credit reporting agencies must put a freeze on the information of children under 16 within 30 days.

Del. Craig J. Zucker (D-Montgomery), who sponsored the bill in the House, said it should deal with the growing problem of child identity theft. Similar legislation was sponsored in the Senate by Sen. John C. Astle (D-Anne Arundel).

Darryl Fears contributed to this story.